The story pops up now and again on social media as a subject for the ten-minute-hate, and a justifiable one too. Someone stiffs a waiter or a bartender and tries to excuse themselves for doing it. Someone signs the credit card receipt at the restaurant and puts a zero in the space for a tip, writing in “I give my money to charity” or “I save my money for Jesus.” Or they give a supposedly principled reason, like “I don’t believe in tipping” or “Your boss should pay you better”…