Reform School for Tightwad Tippers

Dear Helena,
I tip about 20 percent on meals, including alcohol and taxes. One of my closest friends (and frequent restaurant companion) typically tips about half the amount I do, and doesn't believe in tipping on alcohol or tax. I think he is cheap and uninformed but otherwise a great guy. What would you recommend?
—Respect Your Server

Dear Respect Your Server,
You're in the right: The diner should tip somewhere between 15 and 20 percent of the final total, including alcohol and tax. This is widely accepted, which is why the rumor that Oprah advises tipping 10 percent caused massive outrage.

But I doubt you'll have any luck persuading your friend to change his ways, any more than you can argue your uncle out of his political opinions at Thanksgiving dinner. Like someone's politics, his or her tipping philosophy is often more emotional than logical. It was probably ingrained in childhood. That's why people who grew up in countries that tip 10 percent have a hard time changing their ways. For instance, Stefan Smith, a sound designer who grew up in London and now lives in Oakland, California, still tips UK-style when dining alone. (It's another story when he's with his American wife, as you'll see below.)

Anyway, here's what will happen if you try to convince your friend by dint of rational argument and hard evidence: He'll just disagree with or dismiss whatever you say. For instance, if, next time the two of you have dinner, you ask the server how much people generally tip and he confirms that it's 15 to 20 percent, your friend will probably retort: "Of course the server is going to say that—he wants to make money."

I did my best to persuade Smith to up his tip, but for each of my arguments, he had a counterargument. The conversation just went ’round and ’round in circles. It wasn't very likely that I would succeed where his wife had already failed. As an American, she tips 15 to 20 percent. She has managed to convince Smith to tip 15 percent when they are dining together, in order to save her embarrassment. But she hasn't changed his fundamental tipping philosophy, and next time he has a burrito alone, he'll leave 10 percent.

So can anything be done to reform your friend? Steve J. Martin, coauthor of the book Yes! 50 Scientifically Proven Ways to Be Persuasive (its U.S. title), says: "In order to change people's behaviors, we should not even think about changing their minds, but just change subtle cues or features in their environment." In the past I've mentioned how gestures from servers like touching the customer can up the tip. Martin says a strategically delivered mint can have the same effect: "Studies show that when food servers leave a small gift like a chocolate and place it down at the same time as the bill, there is about a 3 percent increase in tips. But if they personalize that gift by saying, 'This is especially for you,' or if they leave one mint and come back and say, 'Actually, here's another mint for you,' tips rise by 12 percent." Another way to increase the tip is to "repeat back word by word exactly what the diner ordered," says Martin. For example: "So you would like the Caesar salad with grilled chicken, and a refill on the bread." If you've spent any time talking to highly trained customer support people on the phone, you've probably noticed that they, too, use this technique.

Unfortunately, only the restaurant staff can change these subtle cues. So you'll just have to accept this flaw in your friend, the same way you would accept it if he was chronically late.

But though you can't change your friend, you can change your own behavior. If he's paying, sneak back and slip the server a few extra bucks. And if you're splitting the check, just leave a really, really generous tip to make up for his piddling one.

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