I've been in restuarants were I literally had to go through a list for any one to know what I was talking about. For example, I once tried ordering Pepsi, Coke, Sprite, Mt Dew, Cola, Pop, Soda, Can, and finally, exsaperated, asked for an RC and was thusly served.
So I call it what the locals call it. . . until they make fun of me for being a yankee. Then I call the fucker a pop and they will deal with it.
Off topic:
RC Cola is the best fizzy concoction I have ever tasted. You should try it some time.