My husband and I have tipped service people who have set rates and charge accordingly. I think a tip is appropriate under certain circumstances.
Guidelines for tipping are somewhat baffling, in my opinion.
As a harpist, I provide a service and charge competitive rates. I don’t expect tips, but sure do appreciate them when I get them. I’m sure there’s a lot of people who feel musicians are paid plenty enough so therefore won’t tip on top of our requested fee.