I have never understood the "If it's posted publically then anyone can respond any way they want, and if you don't want strangers responding you shouldn't post publically" argument. It's tantamount to saying that you can't have a conversation in any public place, ever, without expecting everyone around you - people at the next table, people walking by on the street, people in the next apartment over if your walls are thin enough - to stop and join the conversation. So theoretically, if any of us ever want to have a conversation that we don't want the whole world joining in on, we have to have it in whispers in the corner of someone's basement at midnight, or in a soundproof room.

That's nonsense. Joining in the conversation of random strangers on the street is not, and has never been, acceptable social behavior. In terms of electronic conversation, when phones used to be on party lines and ten houses in a neighborhood shared one phone number, it was understood that people might listen in on conversations that they weren't involved in, but that doesn't mean that (a) they had some sort of moral right to do it, (b) the people they were listening in on had to be happy about it, or (c) that it wasn't rude, creepy behavior.

People often confuse having the power to do something with having the right to do it. Yes, anyone has the power to respond to a public post. I have the power to some random person walking by me in the hall at work that pink makes her look like a drunken elephant. Do I have the right to do it, or to join in other people's conversations in the restaurant, or to walk up to people in the street and give them my thoughts on yaoi? Not under any social contract I am now or have ever been aware of, no.