body: In the US, there is an expectation of almost always tipping certain service providers like waiters and bartenders. Generally, it is expected that customers tip 15% for ordinary service, 20% or more for great service (or when in a large group), and even poor service is supposed to merit 10%. Tipping nothing is considered appropriate only for extremely bad behavior from the service provider.
  
  
  Whenever the topic comes up, many people are enraged at the suggestion of not tipping. It's not unheard of for service providers to harass the customer or even throw them out for refusing to tip, and it is easy to find people claiming that they go further and sabotage the customer by spitting in their food, deliberately serving them very poorly, trashing their car, etc.
  
  
  My question is 2 part:
  
  
  * Is there any legal obligation whatsoever for the customer to tip? I know some businesses have a mandatory minimum tip or service charge which is clearly shown in writing, I am excluding these from my question.
  * Is it legal for the employee to retaliate against a bad tipper? Even if the customer tipped nothing, they still paid the price of the service, part of which covers the employee's paycheck as well. What minimum level of service is a customer reasonably entitled to expect, legally speaking, even if they do not tip?
  
  
  
title: Legal consequences of not tipping in the US