I'm going to counter with: illiteracy, specifically the kind of illiteracy that makes people take a collection of legends and wisdom writings as absolute historical fact.
Is that why scientists would say that there are no ghosts or aliens only because they never seen one themselves but I have never seen a scientist attend an exorcism to double check their little theories on the unseen?
All the people that don't take the Bible as a literal fact. And then there are those who for whatever reason might know it's fact but go to work for the dark side entities. Astrologers, gypsies, fortune tellers, mafias, organized criminals, scammers, thieves, pimps, robbers, drug dealers, cults, religions which deny Jesus Christ as the Devine Intervener. All kinds of things like that.
