Curious how many people ever really did the complete routine on a stability ball vs a bench? Any epic fail stories?

Everytime I see someone on the ball doing incline presses I wonder, who actually did this in real life? There were certainly some other even less stable exercises they would attempt on it.

I always thought it was funny that they didn't have the ball guy ever do actual ab work on it as the primary and the bench be the modification. That would have made (some) sense.