That's obviously because a lot of people have religious beliefs that make more sense to them than evolution. It's not that they haven't heard of evolution, but that they reject it for the simpler theory found in their 3000 year old book.
IME, that's because most people haven't ever heard any reasonable explanation of evolution. They honestly believe that evolution is just "random things happened and fish decided to walk on land". That "animals wanted to see so they randomly got eyes". Given that explanation of evolution of course they're going to reject it - that explanation is nonsense.
Creation is only simpler if you exclude the axiom of having some omnipotent creator in the first place.
