I swear by default. After awhile in the heavy metal scene it just becomes part of your daily speech and guess what i was part of for most of my teenaged years. I also overide the censors because i'm anti-censorship when it comes to language. So while I know your post isn't dircted at me i just thought i'd point out that even people who can speak English fluently, are well over the age range where swearing is "cool", and care not about attention can have a swearing tendancy. So by that i hardly take mass swearing as a stereotype, but again that's just due to my personal conditioning.
To be honest, my main problem isn't with swearing itself, but when people use it. There is a time and place for everything, and I can understand using swears, but if one of the first things I hear directed towards me by someone I don't know involves a few swears that are probably there for insulting reasons, I won't take kindly to that. Swearing isn't going to make me blacklist anyone, if it did I probably should have gotten off the internet a few years ago, but I do care more when people don't act nice around strangers.
Which probably means I should edit that to "People being rude = Jerks", which is extremely redundant.