Quoted from DefaultGen:

I was playing an intense game on location, nudging the machine and such. When I do this of course the people playing next to me start randomly shaking the machine like that's how you're supposed to play pinball, just give it a good shake to let the game know you're there. One of the four people playing got multiball and clearly no one in the group knew what multiball was. He immediately drained then the next player asked what he did and he said "I don't know, I just shook the machine pretty hard and I think some balls came loose". They all kept shaking it. That's one of the dumbest things I've heard.