Dude, that's what's awesome about it. Chinatown is awesome. So is Latino town. How boring would it be if everyone acted all Western European.
Oh, I agree with that (never been to Chinatown in SF, but Chinatown in DC is fun). But it's difficult to describe the difference between integrated cultures, like Chinatown, and isolated cultures, like we're starting to see. There are places here where I would probably enjoy shopping, but they make you feel unwelcome and there's no common language (I speak English, German, and some broken French but the clerks either don't understand any of them or pretend like they don't).
When I visit a foreign country, I at least make some attempt to follow the customs. If you're here in my country, you should at least make an effort to tolerate ours.