Why would you care? Waiters don't expect tipping as much as in the rest of the country.

Hopefully, that'd be because the majority of restaurants are including a service charge with every meal, and not because the waiters have become inured to their techie clientele being chiselling niggardly prats. In circles I move in, being a bad tipper is right up there with shoplifting, dog-kicking or vandalism as a moral failing, and how one treats service employees a touchstone of one's character.

You should change friends. People shouldn't decide what you do with your money.