Acceptance of mythology?

As already said, both Tolkien and Lewis were dedicated Christians, so if there happen to be Christians out there who don't approve of their books...well, maybe the allegory is too subtle for their narrow minds.
As for Harry Potter, yes, the magick is much more theatrical and obvious. I'm a Witch myself actually, and you know what? Any Pagan will tell you that real magick isn't like that (although it would be sooooo much fun to be able to fly on brooms
and stick pig's tails on people we didn't like, wouldn't it?)
That's why they call it F-I-C-T-I-O-N, folks.
Harry Potter is a fun read so I say what the heck?
(not on a literary level with Narnia or LOTR but I still love them).

Anyone who bans books because of the author's alleged religious beliefs is missing out on a lot of fun.