Well it didn't have to -- but what he ended up doing was a ridiculous mishmash of both styles (you've got that awful rabbit chase thing, and then cut suddenly some giant black shadow is murdering Gandalf while trumpets roll). Shoulda stuck to lighthearted etc etc, lots of jollity, like the animated one from way back. But then they made it longer, added grim backstory that in the book Hobbit is never mentioned because it's too depressing for children and it was all over.
We watched the first one on Amazon. My wife kept glowering and we'd have to pause it so she could fill me in on stuff from the Similrilowhatever. We didn't do the other two. We might at some point. Worth noting: She had three pound puppies named Frodo, Bilbo and Radegast, as well as a Cabbage Patch Doll named Galadriel. You two would probably get along.