[bombcar]

Rowling apparently maintained some artistic control on her movies, whereas Tolkien had sold the rights entirely, so Christopher didn't have much of a say beyond complaining.

I think the thing that really "solved" it for me was realizing that the vast majority of the people who watch LotR will never read the book, let alone the Silmarillion. And those who DO decide to read those after seeing the movie - the movie won't destroy it for them.