I don’t mind tipping waitstaff but hate all the tip cups around town. I know I do not have to put anything in the cup, but its begging and that’s tacky.
I sometimes go to Peet’s Coffee to buy a cup. They serve a variety of different blends, but sometimes one blend I want is not made up. The person at the counter will fix a pot of it if I want a cup, so I will put a tip in the jar for doing that, but not just for serving a cup of coffee.