Here, in no particular order, are my maxims concerning the practice of tipping.
1. He who is too cheap to leave a tip in a restaurant should cook for himself. That being said, there is no legal obligation to tip, nor should there be. Is there a moral obligation? Perhaps. Rather than argue that there is I will just state that tipping is the morally decent thing to do, ceteris paribus. And it doesn't matter whether you will be returning to the restaurant. No doubt a good part of the motivation for tipping is prudential: if one plans on coming back then it is prudent to establish good relations with the people one is likely to encounter again. But given a social arrangement in which waiters and waitresses depend on tips to earn a decent wage, one ought always to tip for good service.
2. Tip on the nominal amount of the bill, not the amount less a discount. You got the discount, you skin-flint coupon clipper, don't be so cheap as to demand a discount on the tip as well.
3. Tip no less than 15%. But when in Rome, do as the Romans do. In Turkey, 5% suffices and more might be perceived as ostentatious. And in some places, a tip is an insult.
4. Do not hesitate to leave no tip or a measly tip to punish poor service. The whole point of tipping is to reward good service and to encourage good service in the future. If I have to beg for a second cup of coffee at a breakfast joint, or am reduced to swiping silverware from adjoining tables, then I am not inclined to leave much of a tip. Lousy service, lousy or nonexistent tip!
5. Tip on the entire bill, including alcoholic beverages, unlike a cheapskate I once knew who tipped only on prandials but never on potables.
6. At buffets, smorgasbords, and other self-service establishments, one should also leave a tip depending on the services rendered. In such places I sometimes tip less than 15%. Why? Because I do more of the work.
7. What about tipping on a take-out order in a sit-down restaurant? My inclination is not to tip there any more than I would tip in a fast food joint.
8. Tip the bartender, but if he complains about the size of the tip, tell him to go to hell.
9. I always travel light and carry my own luggage. This obviates the tipping of bellboys and other baggage schleppers. But a hard-working maid who has just done up my room may garner a few bucks.
10. Tip the barber whose floor is now littered with your long hair. I exercise my frugality by having my hair cut only four times per year. I've been known to go to barber colleges for cheap haircuts. There I can play the big shot and leave a 100% tip. If you are ever in Mesa, Arizona, check out Earl's Academy of Beauty.
11. Discount Tire around here offers a great free and friendly service. They will check your tire pressure including spare and inflate if necessary. I always give the kid a $5 tip. They also fix flats for free. I tip the guy who does the work $5.
12. I tip my massage therapist $15-20 for a 90 minute session. More at Christmas.
13. Having driven cab, on the mean streets of Boston no less, I always tip taxi drivers unless they are surly pricks in which case they get zilch. I once tipped a taciturn Jamaican two bucks on a twenty dollar fare and the guy had the chutzpah to complain. I told him to shove it.
The most I ever tipped a cabbie was 20 semolians on a short airport run to McCarran in Las Vegas. He was an interesting character and his conversation was scintillating. I asked him to name his tip. He said 'twenty' so I gave it to him. It is worth remembering that there are people out there who actually work for a living. We can't all be men and women of leisure.
"Your Tip So Far"