>I don't see what civilization has to do with it.

I was referring to The Submarine Captain's remark, above.

Tipping is symbolic of a superior-inferior (master-servant)
relationship. Note that you would not tip your neurosurgeon, or your
architect, or your Senator, or the conductor of the New York
Philharmonicafter a concert. If you tried, those folks would be
insulted, because you've implied they are socially your inferior.

vince norris