It depends on the audience. If you're telling a joke to friends you know their humour and their backgrounds and what will and won't hurt them. If there's a possiblity that someone might be hurt (and there's a big difference between offending and hurting), why tell it? It's going to upset someone and make you look stupid and offensive.
At home in N. Ireland, amongst my friends who are a group from many different backgrounds, there's slagging and teasing about religion and upbringing, all based on perceived stereotypes which we KNOW are completely false. Anyone listening in who didn't know us would think we were being sectarian and offensive - but that's part of the group's collective humour. To the participants, it's not hurtful. Each gives as good as they get. If we were unsure how such teasing would be taken, we'd stop. I've known these people for years and we all know each other's humour. It's when we step outside that group that none of us would ever dream of saying such things.
It's like Ma jokes. (I presume that's a universal thing - where one person slags off the other's mother in more and more outlandish ways. It can be used as an insult, yes, but we go over the top and make incredibly stupid remarks.) Ma jokes are a staple part of N. Irish humour amongst the people I know and work with. Entire days can be devoted to adding "Aye, yer ma!" on to the end of every sentence. And we'll happily particpate in such trivial insults for hours on end, despite the fact that we know and respect and like the other person's mother... But would I say such a thing to a stranger? Not a chance!

and Are You Being Served is NOT funny... :-)