A fair few people dislike displays of intelligence, especially intelligence for intelligence's sake. Recently, my intelligence was recognised and utilised. Then, I was appreciated. Previously, when I have shown brainsmarts about a variety of topics, some people become stando-offish, as they see my show of intelligence as a slight on theirs, as if I'm saying I'm better than them. I have felt this irrational dislike of a smarter person maybe twice, because although I am quite intelligent (in all honesty) I never achieved super-highly in academics (a 2-2 science degree). In practical situations other people can see my smarts, but I'm nice about it and occasionally pretend I'm less able at something, so the less intelligent don't burn me as a witch. And apparently it's poor form if someone tells you you're smart, to answer back "yes, I know" (which is why people didn't get on with Sherlock Holmes).
It's the inferiority complex, or the alpha response, because most people think they're pretty okay at everything. If you can't do something difficult, then someone comes along does it quickly and with no hassle, how do you maintain your ego?