The problem is those that seek to persuade others that evil, the occult, and demons do not exist and that they are the stuff of harmless fantasy, especially when those individuals claim to represent The Church.
When it comes to protecting one's soul, or that of one's child you had best be sure that what you expose it to is not harmful. If there is the smallest doubt that it is not good and pleasing to the Lord, it should be rejected. There is little room for error, for the stakes are eternal.
"There are two equal and opposite errors into which our race can fall about the devils. One is to disbelieve in their existence. The other is to believe, and to feel an excessive and unhealthy interest in them. They themselves are equally pleased with both errors and hail a materialist or a magician with the same delight." - CS Lewis
Such as, seeing devils where no devils exist.
There is not a boogeyman under every bed.
We certainly wouldn't want anyone to teach children that demons are fantasy. What would be next, the Easter Bunny?
Speaking of church ladies.... I think one of my favorite conversations to overhear in my church were two older ladies talking to each other. One asking the other if she got to see the new Harry Potter movie with her grandchild. I never thought I would hear someone talking so excitedly about it. It was so cute.
"There is little room for error, for the stakes are eternal."
I believe Jesus established that faith in Him was the pinnacle of importance for the soul.
Reading other books is not condemned, and having a fantastic imagination is not going to send a follower of God to Hell.