Apparently, this barren land is the closest thing the aliens could find to a major population center in Africa. That's because for Hollywood, the entire continent hasn't advanced much since Jesus was still around. The opening to Casino Royale, for instance, introduces us to Africa with the image of a bunch of black guys betting on a fight between a mongoose and a snake.
We're not sure why they even had a title card telling us the location; this is all we needed to see.
The one area where Africans have caught up to the rest of the world is guns: They don't have any modern buildings yet, but they've figured out how to attach a rocket launcher to the side of a truck. This is only natural, since half the continent's population consists of corrupt soldiers.
Contrary to popular belief, Africa's chief export is not lead.
Congo, Black Hawk Down, Blood Diamond, Hotel Rwanda ... all these movies spend the whole time telling us that Africa is scenically beautiful, but terrible in every other way.
So What's the Deal?
In the same way that Hollywood needs to dumb down a novel to turn it into a hit film, they also dumb down Africa's reality, because they assume that you'd be bored by a realistic portrayal of the continent (or you simply wouldn't believe it). They do have things like poverty and corruption and giraffes in Africa, but they also have universities and industries and modern cities, like Nairobi:
Mutua Matheka, Africa is a Country
Every building is made out of rocket launchers.
Imagine if every single movie set in America was filmed in Alaska and focused on gang violence -- that's how Africans feel every time they watch a Hollywood movie about warlords fighting in the desert. Which is a problem for their tourism industry: A board member for the Association for the Promotion of Tourism to Africa even takes the time to explain that there are "middle class people in every African country commuting to work every day, complaining about taxes and watching their kids play soccer every weekend."