[Porsche-O-Phile]

How is that different from any other industry?

Not saying it's justification to be cheap but the "it's feast or famine" argument can be applied to just about anything.

Tips are for service. If the service is truly poor, it shouldn't be rewarded, but the caveats are, "did you give him / her a chance to make things right and express what was wrong?" and "was it REALLY poor or is it just a case of unfair expectations?"

That said there have been a few (very few) cases when I've not tipped and spoken to a manager (and yelp).