Yes, I have seen examples of this.
Back in 1981 when I studied at UTS Sydney, there was a games room for students which was carpeted. A student one day went to put a coin in a Space Invaders and found 40 credits pop up on the screen when the coin came neer the slot. The next week or so, news spread fast and many students would rub their shoes on the carpet to get a static build up for free games. The static would arc from their finger to the coin slot. I doubt this would have worked in hot and humid Qld. but on a dry wintery day in Sydney under ideal conditions it did.
After a few weeks, the operator got a whif of what was happening and did something in the coin mechanism to stop this rort.
