I suppose that this could also be titled "professionalism" or, if you have a theater background, how to avoid breaking the fourth wall.
Whenever a person works with the public, there is, by necessity, a distancing that occurs. A service person needs to be clean, prompt, knowledgable and friendly. This does not mean going out with or putting the moves on your clientele. A little flirting is alright, as long as its kept at a low, ambiguous level.
They are not there to learn about your divorces or political ambitions or the details of your last surgery. They are there for you to make them feel better about themselves. If that means you have to listen to them rant about their dog, do it. But, this does not mean going out with them after work.
One of the best analogies I've heard from this is crude, but appropriate. "Don't shit where you eat."
This means that you don't pick fights, ask out or try and humiliate your clients. While we're at this, don't bash your peers, either. It's cheap and it makes people uncomfortable. Instead, try and alleviate their fears by being even more confident, and above all, professional.an