Such words have their uses, but I'm lazy and don't feel like vocalizing a "big" word when a "small" word is more efficient and more likely to be understood/facilitate communication in the first place.
I think that's the root of the problem: using a "big" word when a "small" word will fit just fine is more likely to hinder than help the conversation. Then again, it can be very revealing. I have a dear friend of the sort who refers to (musical) records as "documents", and there was a conversation about cartoons and he said that he wasn't a "student" of cartoons so he didn't really know anything about the one in discussion. In saying that, it demonstrated that he didn't just slump on the sofa and laugh his ass off along with the rest of us but would have been taking it terribly seriously, and hence the whole idea of being simply entertained by it would have sailed right over his head.
Though clearly not enough to avoid misusing the word "myself"

Im opposed to the modern aversion of intellectualism.
And, evidently, equally opposed to the use of apostrophes. (Shall I stop teasing you now?)

Am I an intellectual? Yes.
Am I trying to be smart? Yes.
If youre not trying to be smart you are content being stupid.
I think the counter-argument to that is demonstrated in my reply here: you are using language to show off, which puts any mistakes you make under a scrutiny they wouldn't otherwise invite. You therefore run the risk of falling victim to good-humoured teasing when your grasp of the language isn't
quite as strong as you assumed it to be.
That's why people call each other "pretentious" - because those who are very self-conscious about their intellectual abilities are almost never quite as smart as they think they are. Of course, extremely clever people do use a wide vocabulary, but it's not something they're self-conscious about, and if they can use a simple sentence to convey the same meaning, they will. The best way of using a language is to use the most apt expression to be clearly understood. Having a wider vocabularly facilitates that, but if you abuse those extra resources by using them when they are not needed, it can backfire.
I still love that line from The Simpsons:
"Oooh, a
garage."
"Well, what do
you call it?"
"Car-hole."