Personally I'm not afraid of extremely intelligent people neither do i get scared of them. On the contrary i envy them, i try to learn from them and get close to them. I try as much as possible to even supercede their level of intelligence.
I'm a kind of person that challenges my limit a lot and whenever I come across extremely intelligent people i don't feel intimidated, i don't feel hatred, i don't see them in bad light what i see is motivation and an opportunity to push my limit once more.
Coming across extremely intelligent people just gives me the necessary motivation i need to be better than i was. This could be because i could be termed as someone whose intelligence is over average and always willing to be the best of the best in my field so i devote my time to expanding my horizon and knowledge base through reading and experience.
In a nutshell i don't get scared of extremely intelligent people instead i get close them, learn from them and emulate them.