People also aren’t entitled to tips. Regardless, I’d happily forego the “service” of bringing over a tray of food for a 15-25% discount, especially when “good service” is considered interrupting your meal to ask how it’s going or refilling your water (again, something I can do myself and it’s not like I’m drinking gallons of water).
I typically tip around 20% when I have to go for an occasion, but otherwise I don’t go to restaurants.