What about My Little Pony inspires a huge number of people to write, read, and discuss cartoon pony rape fanfiction? I understand Rule 34, and the fun of subverting existing works... but how do you get from subversion funtime to extensive discussion and creation of volumes of rape fanfiction built around a children's show? Am I the only one who sees the boundary being crossed there, into Not Okay territory? On a related note, I've some exposure to the furry fandom as well, having helped a friend manage a sales booth at conventions. I know firsthand that the better part of it isn't built around sex and sexually deviant artwork, but anyone who says it didn't find a solid representation there would be lying. A cursory Google image search, with safesearch turned off, will indicate that as well.
Tolerance is important, especially tolerance of things that falls outside our comfort zones; it's important to recognize things that make other people happy, even if you find them offensive, and let them be. Still... when it comes to stuff that clearly crosses lines for you, isn't it unfair to be expected to turn a blind eye to it, and not express that? With regards to the internet, I have to imagine that the prevalence of stuff that goes beyond the Inappropriate But Fun zone, and enters the Socially Maladjusted/Deviant zone, comes from an unwritten code that says we should just accept/ignore anything we find too weird or creepy, since nothing forces us to expose ourselves to it if we don't like it. Where do we draw the line, though? When does it become enough of an issue that we have to pause and say, "Actually, that thing you said or did there seems pretty messed up to me. Why did you do that? Can we both figure out what things are wrong here, so we can avoid them?"
I guess the heart of the matter is this: Does our social contract allow one person to tell someone else that they shouldn't do something, if they find it offensive or distressing? Where do we draw that distinction?