I just came across this interesting thread.
While what the OP described sounds appalling, I can assure you that for a minority in America, this is a daily occurrence, and not just on the planes.
People don't know what it feels like to be a minority until they experience it themselves. So, now you know.
These flight attendants probably experienced racism the moment they stepped into the states. A few months ago, an extremely polite Japanese woman was asking for assistant from the station operator at a NYC subway station and tried as hard as she could to throw out all the English vocabulary she knew. Instead, she was greeted with a stare and "ain't nobody know what's coming out of your mouth"
I went over there to help her.
Can you blame them?
Get over it.