I have found the opposite - Though I don't think it is as much about my tipping, which is decent, but more about the fact that I am friendly, I smile, and I am appreciative...
And then in another response you don't seem to like bigots?? if you want to crap on generosity and kindness - well, that says a lot about you - right?
It makes me feel better, it makes the recipient feel better - but thanks for your permission...