The OP's thread is just stupid, no way around it.
As many others have said, most basketball players are black because those individuals are currently the best at basketball.
I do not have accurate numbers at hand right now, but i think that the majority of top-pro tennis players are white.
Same goes for hockey i guess... i heard that chess is also white dominant, but that is not a physical sport.
The sterling guy got fired because his statements were bad for business.
Most basketball players and fans are black, and it was definitely a wise business move to get rid of a PR nightmare like sterling.