When I can afford a meal at a restaurant that has servers? Generally 20% AND I bus my own table regardless.
I went to a new, delightfully gay hairdresser recently who spent two hours on my own personal episode of Queer Eye for the Less Queer Guy. You bet your little bippy I tipped that man 25% and scheduled a cleanup appointment.
Personally, the only thing that causes me to go from "nice" to "mean" is intolerance or abuse.
Its not "nice when they aren't mean." It's "nice until they/their community are legitimately threatened."