I dunno, I know a lot of Asian people who are born here [America] but speak their mother tongue. I think a lot of them very into that "Asian pride" thing, or maybe they just want to stick to their roots. Sometimes it's also a feeling of being in a group that is like you, being surrounded by people like you.

I am Chinese, born in America, but would prefer to speak Chinese to my Chinese friends, whether they were born here or in China or whatever.