While I'm thinking about The Hobbit, I'd like to share a revelation I had the fourth or fifth time I saw the first one.

I believe that Azog is a distant relative of Voldemort. He looks like a buff version of Voldemort. Plus, everybody says that Frodo looks a little like Harry Potter. So, I think that modern day wizards and witches are ancestors of people from Middle-Earth. Maybe Middle-Earth eventually became uninhabitable, or it was going to be destroyed to make way for a hyperspace bypass like in The Hitchhiker's Guide to the Galaxy, so they had to evacuate, and they all moved to Earth.