Re: Missouri, yeah, it's baffling here. Versailles = Ver-sales, Lebanon = Leb-uh-nin, Kimbrough = Kimbroo. People are really assholes here if you don't know how to say things in their peculiar, messed-up way. It's not bad in the cities, but outside of KC/STL/Springfield, if you speak standard American English, people are pretty rude. I swear, when I moved here from CO people treated me like I was a Martian.
In CO, everyone said "Say-zahn" which is probably why it's so weird for me to hear everyone say "Say-sawn" here, with a stress on the middle s. Say-zahn is at least closer.
And yeah, I hear you on the whole "correct pronunciation sounds pretentious" thing. If you order a croissant from an entrepreneur, with proper French pronunciation, you'll sound pretentious. I think it's just as pretentious to go out of your way to deliberately mangle the French, like RAM described in Texas court.
@Bboy - the n is like, barely pronounced, in your nose, not with your tongue touching the top of your mouth, like a "regular" n. For the nasal n, you tongue shouldn't have to move.