I don't know about "serious" money but I was good enough at Xevious in college that people would give me quarters to play so they would watch.

I switched to pinball and learned how to find machines that were hard to tilt and would put up the kind of high scores that people would think were impossible. I found that if you played like that at a state school they would threaten to kick you out of the gameroom, but if you did that at an Ivy League school (grad school) nobody would confront you about it.