I hate trading in games, and I'll only ever do it as a last resort. The last thing I majorly traded in was my Wii, but I did that with no regrets because I didn't even touch the damn thing, and at the end of the day? I got an Xbox out of it. So It's all good
But if someone was to say to me "Hey, Meevsy Cakes, why don't cha' trade in some of those crazy Playstation Games that you haven't played in a while? 8D" I'd grab the nearest copy of LittleBigPlanet, start to foam at the mouth and probably crawl into a corner and refuse to come out for at least a week for fear that I'll loose one of my copies. Yes, I love my games to that extreme.
In all seriousness though, I don't know why it bothers me so much. I think I just like to have them so that if I want to play them again (even if it is a few years down the line) I can just simply wander over to my shelf and pick from a wide selection.
Oh, and also, PC games don't really trade in for much these days as well =D
