I like to think that ethnic communities create their own markets for restaurants, and tend to judge authenticity by how many Chinese dine at a Chinese restaurant, Mexicans at a given Mexican restaurant, etc. Sometimes, however, there seems to be a huge dichotomy between the size of an ethnic community and the number of restaurants it produces. Filipinos and Thais seem to represent extreme examples of this phenomenon.
The San Francisco Bay Area has an enormous Filipino community, more that 323,000 identified in the Year 2000 Census, yet there appears to be only a tiny handful of identifiable Filipino restaurants; menupix.com and menupages.com only bring up a single Filipino Restaurant for San Francisco proper (though I know there are a few more in SF and the South and East Bays). On the other hand, a tiny Thai community (less than 6,000 in 2000) generates many times more ethnic restaurants. Menupix and menupages each list more that 100 Thai restuarants in San Francisco alone, with many more elsewhere in the Bay Area.
I can understand that the enormous popularity of Thai food in the community at large, as well as the relative unfamiliarity with, and lack of appreciation for, Filipino food are large factors, but I would think that the size Filipino community (which, if a City, would be the tenth largest in California) would generate a much larger number of Filipino Restaurants than appears to be the case. Do Filipinos choose to eat at home? When they dine out, do they choose a different ethnic cuisine? Do they not sufficiently respect their own food to really elevate it to a "cuisine?"
It's like to hear any thoughts, as well as other examples. Japanese comes to mind as an over-represented cuisine generally, and in New York, Ecuadorean (80,000 Ecuadoreans in Queens alone) would appear to be an under-represented cuisine