I assume you mean that the Harry Potter books are designed to do this? That's funny because my kids and I and my hubby love the stories! The kids saw the movie this afternoon, and I'm going with them to see it on an IMAX screen next week! We've read all the books aloud, and discuss them as we go. Our kids know the difference between fantasy and reality, and frankly have noticed the veiled religious references in the book, that are NOT satanic, but Christian!
Oh, they'd like you to think so.
Theosophists believe in altruism and good humor and brushing their teeth after every meal, too. The problem is they believe in a lot more than that, much of it contained in Rowling's children's books.
But you wouldn't know that if you haven't read up on it.
It's kind of like saying "since a republic is the best form of government, we don't need to learn about communism, socialism or fascism."
Of course, the trouble with this logic is that if we don't know anything about subversive ideologies, we won't recognize them when they try to assert themselves.
And they always do. I've read HP. You guys, for your own understanding as well as your children's sake, should at least spend a little time googling Blavatsky or Frank Baum and his mother-in-law. Just be sure to put "theosophy" in the search line. Or don't.