People reject evolution for one reason - they have a comic book understanding of what science is and how it works, as well as a "knowledge" of evolution that amounts to nothing more than barber-shop gossip. This makes it impossible for them to understand distinguish science from urban legend.

Science has proven itself by far to be the most reliable method for generating useful knowledge about the physical universe. On the one hand it kinda sucks to be an obscurantist. Real science has made obscurantism unappealing. But since most people are too lazy to learn real science, the obscurantists can still afford to quit their day jobs.

Any time scientists can't explain something right away, the obscurantists pounce in with their read-made "explanation." The average population accepts the benefits of science, but rejects it's methods. They are suspicious of science, largely because they don't understand it. It all seems so mysterious to them. As Clarke said, "Any sufficiently advanced technology is indistinguishable from magic." To many people, even very simple and well-understood science might as well be magic.

The obscurantists feed off this ignorance and do everything they can to cultivate it - and they do this in several ways. On the one hand, they point out all the short-comings of "science:"

Science can't answer the 'really important questions.'
Science is materialistic!
Science produces suffering and holocausts!
Science makes people arrogant!

On the other hand, realizing not everyone is going to find this a convincing argument to reject science in favor of the obscure fad of the week, many obscurantists then go about cloaking their own psuedo-scientific opinions in the jargon of science. Advertisers do this a lot. They don't necessarily have to lie; it is sufficient merely to be misleading. Modern day snake-oil salesmen know that that adding words like "scientifically proven" or "space age" or "energy" or "force" to a hard sell will fool a lot of people - especially if they can convince themselves that it's true.

Etymology suggests that science encompasses all knowledge. But many words don't mean (either in denotation or connotation) what their etymologies suggest. Some words have definitions that contradict each other - 'cleave' and 'sanction' for example.

The word 'science' is laden with multiple definitions - and while they are all correct, they are not all related to the activity associated with nuclear physics, advanced medicine, or biochemistry. Obscurantists thrive on the ambiguity. It might be good if people were required to say which version of science they mean when they're talking: Science-1 or Science-2 or Science-N.

Modern science has the de facto status of an Underwriters Lab. But for that to be a useful to society, society needs to learn which version of science is "underwriting" a particular claim.