isn’t it illegal to not give a tip or something in the US? Like, doesn’t a small percentage of the bill automatically go to your waiter/waitress?
The tip isn’t part of the bill. It’s voluntarily added by customers after paying the full bill.
Its voluntary like saying please and thank you and generally being a decent person. You don’t have to do any of these things but people are going to think you’re an asshole if you don’t.