Fuck

I started tutoring these two boys in english last week (kid previously mentioned) - after going over their english homework I was just talking in english with the older kid and he was telling me about his summer camp and how everyone there just said "fuck" all the time. He said to me "Yeah, I thought fuck was a really bad word- I didn't realize you could just say it all the time like that". I then tried to explain to him that it was considered a really bad word- but that for certain people in certain contexts (like possibly pre-teens at a summer camp) it might be used a lot. But he still didn't seem very convinced when i said that it still wasn't a good idea to use the word unless you were sure it was ok. I wanted to say that if he used the word it was likely that some people might sort of look down on his vulgar speech- but it was hard because his canadian friends seemed to like the word so much. How do you explain to someone that their friends are probably not very respected either? I don't mean to sound condescending to people who occasionaly say "fuck" I just don't approve of it's over-exploitation. But then again that was just my point of view of it- and probably would be this kid's mother opinion too. And what if secretly this kid just wants to rebel against his upper class upbringing and get the word fuck tatooed on his forehead or something? I really shouldn't oppress his freedom of expression. But i probably shouldn't encourage him to say "fuck yeah!" to his english professor either.