Helen
Inkling
Surely since both of those movies are adaptations you're really suggesting that the writers of the novels used it as a writing tool?
I think the "going on a journey" and what happens on it (character-wise) template has been around for thousands of years. I think Tolkien et al used a version of that.
What we call "hero's journey" has come to be identified with Campbell's steps, which I think is only a small part of the larger template.