I generally give 20 to 30% for tips.
We used to hang out with a young couple when I was married . Both of us newlyweds. When check time to basically split the guy would leave no tip on our check. I remember it happening twice and finally telling my wife I was sick and tired of adding extra for their cheapness. Third time out I specifically said, “ Hank you are going to give a tip aren’t you?!” His response was why should we do that when that’s their job? I said if you don’t leave a tip I’m not ever going out with you two again. Never went back out with them again.