Very good question! Well, it may be helpful to make a distinction between legality, understanding one's environment and separating the person from the behavior. For example, its perfectly OK for me to be somewhat, loud, obnoxious and "locker-roomish" when hanging out with my men friends (non-mixed gender company, familiarity and agreement). On the other hand, if I acted that way at work in a professional environment, that would not work out very well. Both behaviors are legal, while one works given the audience and the other would be offensive and rejected. It's me in both situations and the behaviors are both appropriate to the setting. Its not that on Friday afternoons at work we don't laugh it up wildly and be somewhat nutty (stress releases) or on the other hand have serious and meaningful conversation with the guys, but what we don't do is blatantly ignore the environment and the tone that generally exists and is maintained in each. The phrase "When in Rome, do as the Romans do" speaks to respecting one's environment. Comedians are at times masters of understanding this realty and good one's do so by not offending others and invalidating them. If they do, the crowd may jeer or give a response that helps the comedian understand his/her audience, then they adjust and contribute to the audienec's evening. Contribution is the key. That's it! I hope this is helpful. :)