In article T9FJb.149570$ss5.88545@clgrps13, "Paul Keenleyside"
writes:

Why tip for expected average service?

Tips are a reward for exceptional service, not average service.

In every part of the USA that I've been to, tipping is customary in
full-service restaurants and certain other situations. That's for *average*
service.

If the waitress went out of her way to provide extra service other than
carrying a plate of food or a cup of coffee (which is
what she does anyway), why tip?

Because it's expected. In fact, it's so expected that wages for waitpersons are
low *and* the feds expect anyone in certain occupations to report a certain
amount of tip income that doesn't show on their W2.

Tips are for service over and beyond the call of duty, such as being a bit
more friendly to visitors, rather than the run of the
mill service. (Take the order and deliver the food and drink).

Where did you get that idea?

A tip isn't
given to a waitress that is crabby because her boyfriend came home drunk as
a skunk and still has to get the brakes on his 68 Ford pickup truck fixed.

Sure. That's not *average* service - it's poor service.

Tips are an option for extra service, not a wage.

I'll tip if I get very nice friendly service, but will not tip if the
service is average. I tip 10% (that way I don't have to do much arithmetic,
but will round up to the nearest dollar.

15 % is customary.

For taxis,let's say for a $16.00 fare, I'll give the driver $20.00 and he
can keep the change if he gets me to where I'm goin' safely and efficiently,
the cab is well kept and clean. I've been in cabs that should have been
taken off the road, and the cab driver gone through a wash, rinse and spin
cycle a few times.

That's a lot more than 10%!

Shouldn't *average* cab service include all those things?