I now pronounce you Dwarf & Hobbit...oops!

[Rikae]

Originally Posted by Davem

But isn't that the point of a game like this - to explore, to invent, to come up with new things - if you only want 'what happened' then stick to the books.

I think this pretty much sums it up.
Ironically, though I might want to enter Middle Earth for a time, doesn't it cease to be Middle Earth if I'm there, with my 21st century American perspective? Isn't anything I might "do" in a RP context, despite any attempt on my part to make it fitting and Tolkienesque, not canonical? It's maybe part of Middle Earth as a living and growing mythology, if such a thing exists, but isn't Tolkien anyway and I wouldn't try to claim it was.
As far as "hot topics" like same-sex marriage, I can only imagine it would end up being decided through a democratic process of sorts, even if it is informal; if the majority of players look down on something and view it as too far from Tolkien's creation, I'm sure they will put a damper on it one way or another; likewise if the majority want it it will happen. It's a fantasy, after all, even if it is a shared one; people will pretty much do what they want.
But perhaps; if it is not only a fiction created by one man, but truly a mythology, it can be legitimately "extended" by anyone by tapping into the collective unconscious? Are myths discovered or written?