My grandfather plays a video poker game called Deuces Wild and when the payouts are set just right and you play perfect you have a slightly over 100% payout. He has been playing for over a decade in Mesquite Nevada and has been making a slight profit year after year.

When you add in points rewards you can end up doing ok in free steaks and massages. The casino knows he wins and is fine with it. My guess is that they like the fact that he is willing to try and help people learn how to play perfectly (which is not trivial) and that makes the other customers play more and essentially cover the small amount of profit he makes.