Another farm boy with the exactly the same reaction.
Urban legend. Rural people know better.
Qualifications:
Lifetime in the livestock industry.
Live on a cattle farm.
Cows in my pasture right at the moment.
Can recognize bullshit when I see/hear it. 
I worked on a black Angus farm for years. No way in hell can I see tipping one over against it’s will without using a bulldozer.
Another farm boy chiming in. I was raised on a dairy farm in the middle of cow country (southern Oklahoma, north Texas). The first time I heard the term “cow tipping” was in my 20’s and it had to be explained to me because I couldn’t figure out what the hell it meant. And having been chased around by a few angry cows (do NOT, ever!, get between a mother cow and her calf!), anyone who tries it deserves whatever they get.
I also grew up on a farm with cows. It’s an urban legend. As has been mentioned, cows sleep lying down. They weigh hundreds of pounds, and will shift their weight to stay upright if you push on them. Imagine trying to push over a 500 lb block. Now imagine if that block had legs that could move to help keep it upright. Have fun.
The only way you’re going to ‘tip’ a cow is to hit it with your pickup truck.
Apparently the supposed technique involved 1 person tricking the cow by pushing from one side in order to get the animal to exert its momentum against that direction meanwhile the two actual tippers subsequently commence a violent series of shoves from the other side, utterly confusing the bovine and perhaps achieving the feat
My friend in Alabama says it’s just an excuse to get some sucker out of the car and into a cow field, and then you drive off without him 
Next question:
Is snipe hunting real?
Another country boy checking in: I never heard of cow tipping until I moved to the city.
Now, snipe hunting is a different story. One of the most impressive wing shots I ever saw was when a snipe (or timber cock) flew up near my grandfather’s feet. He unslung his shotgun and fired one effective shot by the time the snipe was about twelve feet off of the ground.
I like this theory.
And I can assure you that if it wasn’t the orginal soucre of the legend I intend to put it into play to reinforce it as soon as possible.
Cows are lousy tippers
One of my favorite Cecilisms
About 15 years ago. (I think I was about 18 or 19)
Rural Alberta (Cow country).
Group.
Night.
The cow didn’t really tip over they way a 4-runner tips over, it just sort of stumbled around a little and when down on it’s knees(?) a bit. I think it was dozing off. It seemed really pissed after.
It could have been a trick cow. Or a known dodgy cow.
I was at my friend’s, uncle’s farm. (The friend was one of the tippers.)
I always thought this was a only a joke, too. In fact, I doubted that such a bird a snipe even existed. Then I read Anna Karenina. Imagine my surprise when some of the main characters go out into a Russian marsh to hunt snipe! They did go out in the daytime, though, and used guns, not their bare hands.
And though we’ve now established that cow tipping is an urban legend, did you know that if you walk up to the front of an unsuspecting tractor and make a sudden, loud noise, it will tip over backwards?
This will probably get my man card revoked. There really IS a bird called a snipe, also known as a Virginia Rail. It’s small, fast, has a very long thin beak, and lives in marshy areas.
However, ‘snipe hunting’ in this sense, means you put the unsuspecting boob in the middle of the woods at night with a flashlight and a paper bag. S/He is supposed to put the bag on it’s side on the ground, shine the light into it, and call out ‘Here snipe snipe snipe’. The birds are supposed to run inside…
In the meantime, you leave them lost and stranded, and go drink beer somewhere.
Works with housecats.
But how to the housecats hold the flashlight? 
My housecats don’t drink beer…
Cows are cute. Instead of trying to tip them over, why don’t people snuggle up to one? I’m starting up a “Hug a cow today” campaign to change young minds!