Another thing to consider, is that even with vivid explanations as to how and why a thing is evil, it can incite within a weak minded person the desire to rebel, and seek a twisted form of "superiority". For the greater good of the people, those individuals need to be saved from themselves, and properly guided until they become strong enough mentally, and spiritually to say no to ignorant and detrimental impulses. Of course, at some point, the line must be drawn to separate the weak and misguided from the mentally ill.