It seems that starting from the second half of the 70s, hippies and communes were much less visible.
What happened to them?
Also, I note that people who were in their 20s in the 60s and 70s were in their 30s and 40s (an age where people are more involved in voting and business) during the Reagan administration and the increase in the importance of the financial industry. Were the people people involved in getting Reagan elected and Wall Street just different sections of that generation?
There are some still around.
there were economic, social and philosophical aspects to communes. since many aspects of them seemed in opposition to the status quo they were feared. zoning laws were passed to make them very difficult or impossible to exist (limit on unrelated people at an address, only one dwelling per property).
economic elements are still present in housing co-ops.
social elements are still present in intentional communities.
philosophical aspects might still be present in some who are polyamorous.
some still exist. some have modified to exist within allowed social and legal structures. there are other examples where elements still exist.
while people do change their philosophies and lifestyle there are always sizable amounts of people in all groupings in any generation.
Nobody seems to believe me, but I keep contending that hippies were essentially 0% of the youth population even in the 60s and early 70s.
The vast number of people were what the real hippies called “plastic hippies,” or people who mouthed the words without ever committing to the total package. They grew their hair, they smoked pot, they went to rock concerts and shouted whoooooo a lot – and then on Monday they went back to work and their normal lives.
Only tiny numbers ever lived on communes. And only tiny numbers of them lived there for long. Communes are farm communities and those are large amounts of backbreaking work. It wasn’t that hippies didn’t like work, as the stereotype had it. Intensive small-scale organic farming was dying everywhere by the 1960s. Farmers were mechanizing and chemicalizing and organizing like crazy just to keep alive. Even with a core of intensely dedicated and knowledgeable people, this would have been hard for newcomers to the land to pull off. Most, admittedly, were not dedicated and not knowledgeable, and certainly not intense. Communes have a long history in the counterculture of America (see Brook Farm) and they never last.
In between were the visible hippies, the ones who formed small communities in every city, and ran head shops or food co-ops or whatever. They existed everywhere, but were a negligibly small proportion of the population.
The rest of the population simply grew up and went on with their varied lives. Asking how the hippie generation could have voted for Reagan like asking in twenty years how people with pages on Facebook vote. By then, being on Facebook will be one small aspect of being young and have little to do with their everyday lives and opinions.
The 60s were massively important in many ways because they represented the rise of many serious changes in societal attitudes. The Civil Rights movement was one of the best things this country ever did. It also solidified Republican control of the south. The Womens Rights movement was long overdue, but it created post-feminism which is not tied to any party. Gay rights is still a work in progress. Repressive attitudes toward sex were battered aside, but large backlash groups exist to combat it. The country as a whole moved to what used to be the left, but the world just redefined right and left and created a new normal around a new center.
There were few hippies. There were tens of millions of plastic hippies, yes, me included. That’s the real answer. Nobody much likes to hear it, though.
There were two significant periods of commune founding in the U.S., one in the 1840’s and one in the 1960’s. This Wikipedia entry lists some of the communes from the past and some still existing today:
There was no sudden disappearance of the hippies or any of the attitudes associated with them. Long hair and beards on men or casual dress for either mean or women existed before the 1960’s and still exists today. It may have peaked then, but it wasn’t a matter of such fashions appearing and suddenly disappearing. What else do you consider characteristic of hippies? Marijuana? It was used before then and is still used today. The 1960’s weren’t even that much of a peak in its use. Free love? (I’ll take this to mean extra-marital sex.) Again, existed before and still exists. It’s not even clear that there was a peak in this in the 1960’s. Anti-war sentiment? It’s not clear that there was that much more anti-war feeling in the 1960’s than before or after. There’s not even any clear evidence that the 1960’s were particularly liberal. Anybody who lived through the decade remembers lots of conservatives back then. Gay rights didn’t even become that important an issue until the hippies were starting to disappear. Feminism may have been becoming important at the same time, but it really arose from a different crowd.
Indeed. And at least one person knew it back then:
The Farm still offers a lot of midwifery training - plenty of totally not hippies go there for that.
There are smatterings of those who were serious about the lifestyle around here. According to Exapno I qualify as a plastic hippie as eventually I opted into a more conventional lifestyle. It was nearly a necessity after our children were born unless we wanted to offer them a lifestyle out of the mainstream. And we didn’t.
But I’m not sure the phrase plastic hippie is fair as what makes a hippie exists, not in the trappings, but in the heart and mind. And I still carry basically the same values, with a little refinement birthed from experience, as I did as a young woman.
For me those would be:
Don’t be swayed by any group of people to the point that you’ve lost your personal values.
Be mellow and nice to people and creatures whenever you have the capacity.
Mother Nature is your friend.
Being a healthy human being, spiritually, physically and mentally, is important. (Did hippies get that? I suppose as much as any younger person can. Their definition of healthy differed somewhat from what mine is now.)
Don’t waste the gifts, either material or esoteric.
Play!
There are some still around – such as the Rainbow Children/Family, a loosely-affiliated group of hippies, some nomadic, across the country and the world. An Americorps teammate of mine had traveled with them and lived on a commune back in 2003. Rainbow Gatherings can draw thousands of people. Some no doubt live a more or less mainstream life outside of the Gatherings, but I met people who still traveled in vans, or lived on communes, and even people who were third-generation hippies (hippie grandparents in the 60s, produced their hippie parents who produced them in the 80s and 90s). If you go looking for them you can find them.
There are quite a few communes in Australia, some founded in the 1970’s and still existing and some recent ones. Here’s a partial list:
http://www.communities.org.au/projects
In rural areas of Australia some councils allow “multiple occupancy” zoning, which allows many dwellings to be built on one property even if it’s only one title. The hills behind Mullumbimby have quite a few properties like this and also the farm land around Nimbin has many.
There is also a very famous one in Scotland which is doing very well.
Successful communes and intentional communities exist all over the place, but the most successful ones have strict limits to the number of people they can support on a property, and they don’t advertise or offer public tours. You won’t hear about them unless you know someone living there and are invited to visit…
I hate “just Google it!” answers, but nowadays they’re called “intentional communities”, and their number is growing. I’m going to be starting work soon in a community that has a bunch of them.
Do a search on “intentional living”.
edited: I see someone already mentioned that
In addition, there were any number of people who in any other era would have simply been called “derelicts” or “drifters”, but who in the late '60s and early to mid '70s got called “hippies” simply because they were in the right age bracket, wore the hair and clothes fashionable to their cohort, and maybe preferred various types of drugs to alcohol.
they all got jobs or died off from STDs
There’s a whole lotta them at neopagan gatherings all over the country.
Old hippies are the best, man. 
Exapno Mapcase is pretty much right. Real hippies were far and few between, but they represented an easy counterpoint for the establishment of the time to blame troubles upon.
Popular culture at the time seemed to promote them as some sort of cutting edge, but they were essentially stoners.
Some of the folks that I knew didn’t like being called hippies. They were opposed to labelling.
Exapno, I suppose that I would have been described by you as a “plastic hippie.” I was a high school English teacher and a volunteer at a walk-in “rap house” at night and on weekends. From time to time one of my students would catch me at a movie or on the street in my regular “hip” clothes. There was nothing plastic about either of the roles that I had. If my employer had allowed it at the time, I would have worn my comfy “party” clothes at work. But we couldn’t even wear pant suits, maxi-dresses, or boots to teach in in the late Sixties in Nashville.
By the time I retired, I wore jeans most days. My principal didn’t like it that many of us did, but there wasn’t much he could do about it and we were more comfortable in bucking the system by then. Was I a “plastic teacher” or a “plastic hippie?”
One young man who started teaching the year that I did let his hair grow down to just below his ears. The principal tried to fire him unless he cut his “hippy” hair. The teacher fought it and won.
I still hold the same values that I held back then – maybe even more passionately in some situations. It wasn’t the clothes or the hair that determined my attitude about life.
Gee, where did all the “flappers” from the Twenties go? The question sounds just as silly to me as the question in the OP.
Zoe, I was just responding to the OP and the seemingly common notion that hippies and communes were a dominant element of the 60s.
There was a youth generation, but it was more cultural than social or political. Certainly it skewed toward leftest politician and ideals and certainly many people today retain some of those same ideals.
But your point about the flappers is a good one. I’ve made the comparison between flappers and hippies in other threads. Women in the 1920s threw off a lot of the pre-WWI repression, and their clothing and attitudes reflected it, but that didn’t change the political culture. The economy and outside threats did that.
The 60s weren’t about hippies. They weren’t even about about youth, although they got a disproportional share of press coverage. When people say “hippie” the image conjured is of a particular stereotype about youth. That stereotype never applied to everyone, and got weaker and weaker with every passing year. Even at the time people used to say that hippies turned into yuppies, but that was also a silly stereotype. Yuppies weren’t responsible for Reagan, either, though that’s often said.
If you stereotype entire generations you’re bound to be surprised when reality throws up examples that don’t conform to the stereotype. The Greatest Generation wasn’t. The Boomers aren’t. Generations X and Y and Z never were. In every case it’s the shorthand assumption that leads you into trouble, no matter than you can find individuals that may represent it.
I think it’s akin to all these kids now-a-days where “gangsta rapper” type of clothes and using words and such to emulate the culture. A bunch of suburban white kids wearing their pants around their ankles hardly is anymore than an imitation.
I think that’s part of of the problem. The “Hippie Culture” became fashionable in the 60s. And it became blended with “mods” leftover “beatniks” and was pushed and marketed as fashionable.
So while the hippies were far and few between, their culture or at least the marketable version of it was. The same way the “Thug” culture has become popular today. How many real thugs do you know? 
You could adopt some of the philosophies of the hippie movement without ever being formally part of it.
The hippie movement reached it’s zenith in 1967 with the “Summer of Love,” which according to my San Francisco history book, began in January of 1967 and the phrase “Turn on, tune in, drop out.” was coined by Timothy Leary.
By the end of 1967, the hippies themselves staged a “Death of the Hippie” funeral. The “REAL” hippies decided that the movement was overcommercialized by the “Summer of Love” and was becoming to mainstream.
So in effect “offical” hippies were dead by 1968
You can still find religous communes. Ann B. “Alice/Schultzy” Davis of TV fame, belongs to one and advocates her religious lifestyle.
The comments about the influence parent hippies had on their children are interesting. Our daughter spent about five years on the road with friends attending Rainbow get-togethers and following the band Phish. They dressed in that ragtag gypsy style popularized by my generation and had even stronger ecological values than we did.
While there was a considerable amount of marijuana consumed I wouldn’t call them stoners. To me that implies being so laid back that little gets accomplished. These kids have rejoined the larger community, are independent moneymakers and are weekend hippies.
Their jobs continue to be somewhat unconventional (some in the arts, some in music, agriculture, one English teacher!) But they seem to hold onto their characteristics of dress and attitude more consistently than my generation did.
Perhaps there’s more social permission for them to do so than there was then, what with the slander campaign the older generation initiated against the hippies of the Sixties. There was considerable social pressure on my generation to follow in our parent’s footsteps. It may be that parents are more encouraging with their children to find their own path today.