Why do people deny the theory of evolution?

Seriously, do they devote even five minutes to the study of evolutionary theory before stating that there's no way it can be true? It really seems like the most valid argument I can find basically boils down to "It's too hard for me to understand the scientific principles behind evolution, so I have to attribute it to god". Is that it? Because it seems as though most of the people who don't believe in evolution were either too lazy or unintelligent to even attempt to learn anything about it before dismissing it out of hand.