Here in Maryland, far from the Southwest, we have a traditional Mexican Restaurant that was originally owned by immigrant family from Mexico. I first ate there 60+ years ago. They have been continuously famous for authentic Mexican food.
The clientele is nearly all non Mexican, mostly white.
Two miles away, the clientele at the Taco Bell is about half Latino, and a quarter colored but English speaking. I have been in there when my wife and I were the only customers speaking English. 3 other Taco Bells are much the same.
There are a number of recently opened Latino places, I hesitate to call them restaurants. They are in store fronts, all the equipment seems to have been salvaged from somebody's rehab. The visible part of the kitchens is so messy that my wife will not stay and order anything. Clientele there is universally Latino in work clothes, and the list of items is first in Spanish, with details, then English, with out details.
Spanish speaking customers in other fast food places seem to be well in the minority. Taco Bell seems to be the winner in the Latino population for big name chains.
