When your friends swear while they're round your house

I don't know if its just me, but i have been brought up never to swear unless its necessary. I swear all the time anyway, but i try to keep myself under control around my parents.  

My friends though, they have a different idea. They swear so loudly and for no particular reason, loudly enough for my parents to hear. So because of this, i get a "talk" from my parents about whether i should still be friends with them. it sounds trivial, but it just annoys me so much. Am i the only one?