Yeah I wonder sometimes too. Manners are one of many good reasons that someone may not continue to chat with another person. It's all in the WAY things are said. All this "Oh, s/he said that, but really means this" just makes manners in our words that much harder.
I know this may sound like I'm one of those on the other side, but don't we all end up there one point in our lives, if not at least once?:
I have been emailing a good person on this sight. He initiated the thread. I replied, and we continued to the point of IMing. He was so concerned about himself, and he was asking all these odd (to say the least) questions. I pointed it out to him, and he said he'll try and stop it. In the very next IM session, he did his usual, so I just stopped talking to him.
I know it was not good manners from me, but what could I do, he refused to listen to me at all. So, even though I have been on the other side, this one time, I am still curious myself.

Hope this helps YOUR CURIOSITY.