I grew up in an area that was about half and half two ethnicities with a lot of history between them.
An acquaintance of my dad's went to visit a man of the other race. He was sometimes called a not-too-complimentary nickname by his family, but Dad's friend really shouldn't have been using it.
So the wife answers the door and Dad's friend said, "Is Mr. Nickname here?"
The wife looked over her shoulder and yelled loudly, "Realname! Some [race] guy's here to see you!"
Cracked Dad's friend up, and he got the point.