My first and only ride in the back of a pickup truck was on a camping trip about 30 years ago. Everyone piled in and off we went to Cherry Lake outside of Yosemite–about 15 miles on twisty roads. Not only did I get car sick, but I ended up with a horrible sunburn as well.
Yes, it was a treat when I was a kid if we were with a family friend who drove a pickup.
My in-laws own a farm, and piling all the kids in the back of a pickup is still the standard way of moving them around. It’s a very rural area. I just looked it up, and it’s not illegal in that state.
When I was 10 (1975), my father and uncle bought a hardware store. As part of that, my dad wound up with a pickup truck, which was technically an asset of the store, but which wound up also becoming his everyday vehicle. No cap on it, and we did ride in the back fairly often, though only for short rides (10 or 15 minutes), and only on city streets. Illegal, certainly, but we never got any grief from a cop over it, either.
Along w/ the usual impromptu rides in the uncapped bed as a kid and teen growing up in 1970s/80s SE Michigan, my brother and I rode in the capped bed from Detroit to Kentucky to visit my maternal grandma, usually driving at night (dad worked afternoons). I slept many hours of my childhood on a pile of blankets in a truck bed, falling asleep to road noise (we were well-motivated to do so as ‘Shut up and go to sleep’ was reinforced by liberally applied corporal punishment).
Many times.
Even rode on (not in) the trunk of a car once.
As I read through the thread, I thought an interesting poll would be to see who calls it a pickup truck or just a pickup or just a truck and where they are from.
Yes, on country roads and two-lane highways when we visited relatives.
Also took long car trips riding unsecured in the “way-back” of the station wagon, when we were young enough to use it as a bed for naps.
My parents also thought it was fine to have us sit on aluminum lawn chairs to ride around in the back of the old Dodge van we used for errands when we stayed at our lake house. We would occasionally fall over if they stopped suddenly, but, hey, that’s life.
Many times as a kid just because it was a fun place to ride.
As I got older it was usually when you where moving stuff and it needed to be held in place while in motion. Best one was an upright piano. Had to move it several miles across town and the owner played it most of the way.
Never in a pickup truck, but about 70 years ago my father and I went from Philly to Long Beach Island, NJ, in the rumble seat (google that phrase and look at the pictures) of my uncle’s sedan. There were, of course, no seat belts and I am sure that is much more dangerous.
Sure and I have driven my PU with guys in the back.
Done this only on my uncle’s farm. We often sat on the tailgate. The truck was going very slowly on dirt roads.
It wouldn’t be safe riding on the tailgate on public roads. Riding inside the truck bed with the tailgate up would be OK on back roads. I wouldn’t want to do it on highways or Interstates.
I can’t recall getting a chance to ride in the truck bed on public roads. Would have been fun.
I have seen a lot of dogs riding in the truck bed. That’s very common in rural areas.
The kids always rode in the back of my papaw’s big Chevy when I was a kid back in the 70s-early 80s. We even took a cooler and sat on mats for the 4 hour drive to visit family a few times a year.
Good times. 
A few times, when I was in my early 20’s ( this happened circa 1978-1979 ). I had just graduated college and was living in a medium-large Southern city, but a couple of friends of mine were going through a rural living phase and had rented a small rundown “farmhouse” outside of town - I remember they kept chickens and ate tomato sandwiches all the time.
And they had a pickup truck. I used to ride in the back when we went to the quarry to swim. They kept big oversized truck inner tubes in the back, which we used for seating. They also came in handy as swim toys for the quarry. It was totally awesome.
I must say, and for the record: Never by Choice.
Oops I forgot about the other circumstance when I made my earlier post.
My wife and I spent most of the '90s spending our summer weekends working with some friends at a renaissance faire. The friend who owned the shop where we worked (a blacksmith shop) had a pickup truck, and we would regularly use the truck for quick runs from the faire site to a local truck stop (for showers, and breakfast on Sunday mornings).
Of course. Both sitting down and standing up. Generally for local trips / short distances / 40 MPH or slower, not daredevil stuff.
Every year, deer hunting we ride the roads to get to the far side of the woods to sit for an oncoming drive (woods 1) or to walk back in to the posters (woods 2.) A few years back, Wisconsin made it so we didn’t have to have a case on the gun. Made it much quicker. Unload and go.
Recently, in Antigua.
More times than I could count. Riding on the tailgate is the best.
Many times as a young kid in a standard pickup in the 80s and 90s.
As a teenager working a summer job working on farms (building fence, grain elevators, grain bins, etc), many MANY times on the back of a flatbed pickup between job sites. Riding at interstate speeds on the back of a flatbed is a bit more exhilarating than a typical truck bed.
One of the other trucks we used at that job was a small pickup with a camper shell with a raised plywood platform so you could store a bunch of tools and still have a flat surface above. We’d ride back there and sleep, either on super-early-morning rides to the job or exhausted rides home after a long day’s work.
None of that was too safe, but the stuff we were doing on the job wasn’t exactly up to OSHA standards either, so the ride to and from work was relatively safe by comparison.
Wow, look at the age demographic in the poll results … talk about geriatric …