In my personal opinion swearing shows your intelligence...
Most of my college professors swore like sailors (and ever more than sailors ever swore).
Depends how/where a person grows up. In Pansy countries, swearing is something to be frowned upon, while in countries I've lived in, swearing is just another addition to words. In Serbian, I can swear at least 4 times in one sentence, and not a single person will take offense. No one degrades you for just saying "bad" words.
When I visited the UK, I was amazed at how people looked at me whenever I used the word '****', and I use '****' a lot. Everyone took that one word personally for whatever reason, and treated me as if I crucified their entire family, and forced them to watch it.
Now, if someone were to swear whenever they liked, that would be ridiculous. But if I'm on the streets of London, or in a cafe in Amsterdam, I won't hold back from swearing just cause it's "not nice".
I was brought up to believe swearing is nothing serious. In truth, it really isn't. Every language in the world has swear words. If it were so bad to use them, then why are they there?