For me, it's been a limitation that I've had since I was a wee lad. I learned very quickly that eating lunch before running around with friends at school meant that lunch would end up on the playground.
It's happened 3 times in my "adult-stage." Twice while weightlifting (luckily I made it to the parking lot both times -whew!) and last time, grad school (years ago) doing a 20K run. I'm not a huge guy, but I'm not small either, 5ft 10in, 172lb. I've just always assumed i have smaller stomach than most folks.
I no longer tempt the Gods of Chunder and simply don't eat large meals immediately before, or during, exercise.