There is a whole generation of Albanians that moved in Italy (after the 90s), learned the trade there and eventually moved in NYC and opened their places.
Fun fact number 2: A lot of greek places in NYC are actually operated by albanians. (for the same reasons as above).
The main reason is marketing: People in the US know italian and greek food very well, but they are not familiar with Albanian food (which is just as good), so it is much easier for Albanians to market/open a italian/greek restaurant.