Good parallel. Loved the movie. It was refreshing to have an Indian portrayed by an Indian, for one thing. And a Canadian playing a Canadian, for once.
Actually, if I remember correctly from the notes at the back of the book, the cannibalistic island was symbolic of Islam. But yes, I can see how it could be symbolic of LDSinc. also.
When I read the book I was a TBM and didn't quite get the full meaning.
When I watched the movie I was an apostate and I totally understood it! Spoiler alert! The whole premise is that religion / belief in God isn't true, but it is comforting and gives people something magical to believe in. It is a means of giving the tragedy in life a better spin - or finding meaning in chaos and tragedy. Very profound message and I think the movie was a great rendition of the book.