The internet is in an uproar over a pastor who didn't want to tip his waitress, telling her "I give God 10%, why do you get 18?"
I suppose it could be a hoax - people will take any excuse to criticize the faith - but everyone believes it because of the reputation that Believers have earned for themselves in restaurants. Waiters always confirm this behavior when I ask about it, even the ones who go to church.
Christians are known for being bad tippers. I don't know how something like that can happen, but I know that I would like to live in a world where people who go to church are known for their generosity.