I really hate it when people sell their accounts. Beyond the usual rule breaking associated with it, it's sad to see your friends give up a character they put so much time in to and you had fun interacting with. Like people who delete their characters, they usually regret it. Maybe not now, but in a month or a year when they get the itch to start playing again. Out of the hundreds of people I've met on WoW, I could count on one hand who quit and never came back.
A month or two into Wrath, two of my WoW friends gave away their characters to people at school because they were bored with the game. I sometimes see their old characters in a city or in trade, and it's sad. Although that feeling changed when the new owner node-ninja'd me in Sholazar Basin. Now one of my other friends is considering selling his character he has been playing for three years. Like a lot of people these days, he's having financial troubles (nothing overly serious) and needs some cash. I don't think selling his character is a good idea, but I'm not the one in his position. I really hope he doesn't sell it, because he's invested so much time into this character, and I hate to see my friends make mistakes. I guess it's his mistake to make and ultimately I have little say in it. But I will certainly miss seeing him around on his character. With over 130 days played on my main, I don't think I could ever get rid of her (the fact that I even refer to it as "her" says something) but I guess not everyone is as attatched to their toons.