It also helps to create that barrier that furthers indoctrination.
The difference in language is something that I struggle with too. Many of those that I work and sometimes hang out with (college educated people) feel the need to curse like sailors at times. I still struggle with accepting expletives as part of normal language and using them myself. When I'm reading something online to my wife, I routinely change curse words to something less vulgar even though I know she doesn't have a problem with the curse words. I can see how this serves to keep us separate, create a barrier between us and non-JWs, and gives us a superiority complex.
Interestingly, an elder in my hall was assigned overseas for many years and sh*t was used locally as the non-vulgar word, but caca or poop were seen as vulgar. He had to get used to using sh*t in everyday language.