Saying “I don’t understand the need for slash in Tolkien’s world” is patently ridiculous. Tolkien’s world is our world. Tolkien’s characters are us, or at least our deep ancestors. Complaining about the existence of homosexuality among a human population is like complaining about the fact that we have noses or cry when sad or seek food when hungry. It’s part of human nature. Always has been, always will be.

Tolkien wrote fantasy, yes, so if I can suspend disbelief long enough to believe in immortal beings that make glowing trees and put that light into stones that get stolen and result in battles between dragons and vampires and werewolves and an immortal servant of a dark power who eventually implants himself into a magical ring that gets thrown into a volcano by a Hobbit (a what?) … yes, I can perhaps suspend disbelief long enough to believe that no one in Tolkien’s world was gay.

But pretending like this is the default or only correct way to see Middle-earth is stupid.

Secondly, claiming that slash “disgraces” Tolkien’s world is offensive. It is no different than saying that people who are gay “disgrace” our world. Homosexuality is one of many sexualities observable in the human species. While not the most common (I would argue that would be bisexuality, in a less heteronormative society), it is no better or worse than any other, including heterosexuality. It is simply the way that people are. We have words for people who judge a person as lesser because of the traits she or he was born with.

When people say that gays and lesbians “disgrace” the world into which they were born because they were born as gays and lesbians, we call those people homophobic. I think some people in fandom need to get used to the label.