Perhaps. Or survival of those that adapt to the local conditions - just as there are upper end authentic Mexican restaurants around Greater Los Angeles, the vast majority of Mexican restaurants are straight up tacos and burritos charging half or quarter of the price of the upper end places. Some folks enjoy chop suey and order that. Chinese restaurants in the U.S. are exactly that - sell what you can make and that people order and buy on a repeat basis. Most Americans tastes are fairly plebian.

David