Yeah, I'm big on swear words, but obviously I'm aware of whether or not it's appropriate for a given situation.
IME the people who try to deter you from swearing via whatever social cue they choose to be quite regressive, often in quite a controlling manner, or quite simply just, you know, wet blankets who don't even know why they think it's bad.
At the end of the day, the majority of these words are somewhat relating to sex or human genitalia, and it just tends to show that people have some kind of an outdated attitude towards sex or body parts, which can be incredibly damaging. It also tends to come alongside the attitude of "it's just wrong" ALA why you shouldn't do drugs or anything else pleasurable or hedonistic.
I try not to curse but it's a bad habit I've never been able to stop. If it helps you feel better about it there have been studies done and they say people that curse a lot are found to be more honest than those that don't.
I think that too much cursing makes people sound retarded, like they're actually have sub-human IQ. However, if you have rich stash of words and use lots of different words smartly it can be ok. If you spew out sentences like "Fuck man this fucking thing is fucking annoying shit fuck" you sound terrible