My feelings exactly. It's a 2-way street. I shouldn't expect someone to know my language when I travel, nor should someone coming to America expect me to know their language. I have friends from Venezuela who I hung out with back in college. During one particular party, there were several latin-american countries represented (Puerto Rico, DR, Columbia, Venezuela, Mexico, etc), and for a while I was the only American in the room. Since I know Spanish, they were speaking spanish 95% of the time. When other American's arrived though, they switched their conversations over to English. This was out of respect for those who did not speak Spanish, especially since we were at an American university.
When I was leaving Mexico and was at the airport, my entire conversation at the ticket counter took place in Spanish. Although I knew that the attendent spoke perfect english, I had the respect and knowledge to speak her language.