It's true, when someone mentions South Africa to me the first thing I think of is the country and not the region.
It's pretty much the same thing and I get it, it is a mouthful to say it all out like, United States of America, but when the word America comes up anywhere in the world the thought always goes to the U.S.
I don't know, it's not like a big thing really, I just wanted to see what other people thought about the question.