The actual scam is that restaurants can and do pay wait staff below minimum wage (like 2-3$), because it’s explicitly allowed, with expectation that the rest comes from tips. So not tipping in USA may in some cases be an asshole move.
Tipping is one of those Moloch coordination problems where if everyone would suddenly decide to make the world better at the same time, it would be, but if only a few people try to make the world better, it gets worse and they're assholes.
https://slatestarcodex.com/2014/07/30/meditations-on-moloch/
Wait staff can lobby to change that if they want. Or just get a different job and let supply and demand sort out the wages for the remaining waiters.