In regards to good art being misused, etc... so can good faith. How many people have misused religion to further their own insanity? Yet we don't ban all Baptists/Catholics, etc because a few have been shaky upstairs and abused parishioners, etc.
If I suggested a ban, I suppose you'd be making an interesting point. So long as you try to frame this as an excluded middle argument, you'll be missing the truth as much as the book burners do. Saying that
some children
may be drawn to occultism through Harry Potter or Dungeons and Dragons simply will not make sense to you if you can only think in terms of
all or
no and absolutes.
If I tell you that you skiing is dangerous, I'm not saying that all skiers will die from that hobby. If I tell you that you should excercise caution while skiing or letting your children ski, I'm not saying that you should ban skiing or that no child should ever ski. Can you tell the difference?