Lots of sex? I've seen the walkway between hotel rooms in Puerto Vallarta where they went between rooms while filming the Night of the Iguana. Its a tourist trap like the set location.
IMO most people use profanity because they are borderline retarded and have no respect for others. With that said, I curse a LOT in some situations. Back in 2005 prior to joining the Army I rarely cursed, but it didn't take long to pick it up like a second language. You don't even realize you're doing it; It's just like living in El Paso and ordering dinner in Spanish, even though you can't speak a single proper sentence in Spanish. Regardless of how much a person curses, I only look down upon them when they lack the ability to censor themselves. If someone curses like a sailor in public or in front of elderly or children, then I will instantly harbor a deep disdain for them.
In the passed 25 years I've uttered less then 12 curse words. 8 times it was because I had to repeat a conversation verbatim. The other 4 were my bad. It's just like anything you train to do. Self discipline.
I used to swear but around 1963 when I hit my head on my car bumper while doing repairs I decided I was going to be in control and haven't really sworn since. It helps to work around others who don't use profanity also. Rarely do I hear folks in the medical profession use profanity so maybe an education helps? Beats me, I realized I wasn't going to let profanity control me so I changed. Self-discipline like the guy says...