There will always be stupid people. Believe it or not, some people just wont learn.. Not everyone can get a college diploma from even a decent university, or do/know things that come naturally to others.
Not trying scientific racism, but this stuff does hold a lot of weight and people haven't been able to refute it! From my own observations of people, I find the normal IQ distribution to be a good explation of why people can or can't. It's that simple.