Agreed. I think the “S” is just about making it sound like a plural. Saudi Arabia would be a better addition than South Africa.
For example: while there we stayed a few days in a suburb called Sandton (it's written up in Wikipedia). It's not far from Jo'burg and just down the street from our hotel was a Rolls Royce dealership. Also just a few miles away was a settlement called Alexandra which is identical to a million other shanty towns you can see anywhere in Congo,Nigeria,Guinea Bissau,etc,etc.