Harry & God: The symbolism in HP

An interesting part of Harry Potter (and also a convtroversial part) is the absense of God. I have some friends who go to Catholic schools, and they aren't allowed to read Harry Potter. I've always wondered why that is so.
Instead of focusing on a religion that Harry is able to find strength though, Rowling focuses more on the love that helps Harry to survive the evils. I find that is why HP is so attractive for teenagers. I find that religion sometimes confuses me, and I never am 100% sure with it. Harry Potter series illustrate a world where human emotion drives life, not a God, or an invisible hope. All of the world seems to wonder what it would be like if there was no God, and Harry Potter shows the world what that would be like. TIME magazine addresses this issue and say that "In the new millennium, magic comes not from God or nature or anything grander or more mystical than a mere human emotion."
Another subject of interest about the Harry Potter series is the lightning bolt on his forehead. The lightning bolt has caused concern because in Greek mythology it is known as "Thor’s calling card" who is the god of thunder, rain and fertility. Some are also worried because the swastika is a crossing of two lightning bolts.
Either way Harry Potter books are amazing.