Why do people think everyone from the south is an uneducated retard?

ive lived in the south all of my life,im 14 by the way,and im more politically savy and more intelligent than most adults from the north and south,not everyone from the south is an inbreed hick,granted there are a few,and were not all racist bigots either.i guess what im asking is why are people from the south looked down upon and discriminated by northerners just because we have a different set of beliefs and ideals?