Games in South Africa have to be individually rated by the Films and Publications Board. Mobile App Stores can apply for an exemption from this rating process and self rate (Nokia and others have done so). Apple hasn't bothered:
http://www.thyon.com/blog-entry/items/apples-lack-of-games-m...
There are workarounds for South Africans, some easier than others, but it is very annoying, and Apple never mentions that you can't buy games with a South African App Store account in their advertising.