It's a frightening, frightening thing for True Believers to feel that there are alternate creeds out there gathering more souls and even reeling in apostates than the One, er, Three Good Books.
You know, this summer, I was talking with an eleven year old boy about Harry Potter. He was all excited after the latest movie release and last book release. So I asked him what he thought of the last book. And he said he didn't read it and won't read it as the books are too full of details and description and stuff and he can't wait to see the next movies.
To be fair to him, he's a second language English speaker.
But it gave me an insight into what PJ has done. He's made Middle-earth an experience even for those who don't or can't read English. Middle-earth was unreachable to people who don't know English (or who were dependent upon the frailties of translation.) But PJ has taken Middle-earth out of Tolkien's language-based concept and repatriated it for a completely different kind of territory, one not mapped by language or imagination so much as by sensory experience.
I think this is what might bug the Tolkians, that the word is now gone from the face of Middle earth.
Speaking entirely as someone who has not recited the Creed of Tolkien but who doesn't worship at the shrine of Jackson either.