I guess the eternal battle between Good and Evil is a too far-fetched of a concept for some people.

Perhaps these people are so obsessed with the tropes of the physical world that they are actively restricting themselves from perceiving archetypal truths.

Grey zones of morality exist in Tolkien. Sex and temptations exist in Tolkien. Corrupt politicians and evil rulers exist in Tolkien. They are just not the main attraction because the author has a much more important story to tell.