Being hispanic, but having a light complexion, I haven't really experienced much of this, especially b/c I live in LA. When I have experienced it, it's always been in Asian areas. It kind of gives me an idea of what some people do and have gone through on a daily basis, which is quite sad. A couple of examples:
When I was buying my cell phone from a store in Cerritos, I went to an ATM in a Chinese market. We ask the Lady where it is, she says it's over there, but its not working. My dad says, go try it anyway. Not only was he able to take out $100+ I was as well. The lady gave us dirty looks when we used it successfully, but when we asked her why she said that to us, she kind of mumbled an answer then ignored us :Q The guy I bought the phone with was condescending and mean, untill I had cash in my hand. He was very pleasant and reasonable with the 3 asian people he helped before me.
Getting dim sum at place in West LA. The asian girls pushing the dim sum carts would come by our table once, if at all, to offer us what they had. They woud give it quickly, without explaining the item or what was in it. Compare them to the hispanic men and women pushing the carts. They would spend equal time at everyone's tables, and were willing to tell us what the various types of dim sum were. The asian girls (there were only girls in this shop) were spending more time at the asian customers' tables.
1 dim sum, and 1 korean bbq place in Cerritos. At both, the asian help was curt, and short with us, but visibly nicer to the asian customers.
Contrast this to a couple of good Japanese sushi places in west LA, the attitude there, was always nice, and the chefs and help were very very nice, and treated all the customers well.
My 2 cents.
Now, those of you who live in LA and have gone to non-Asian ethnic restaurants, like Indian, Mexican, etc, what has been the response. If I go to a Mexican place, I will speak Spanish, so I don't know what the reaction is that way....