Some hoarders seem to attach very strong emotional response to each item... They recall exactly where they got it and who gave it to them and the circumstances. Getting rid of the item seems to be deliberately getting rid of a cherished memory.
I've seen that claim made before about hoarders, but with what I've read about people essentially making up memories to explain things, I have to wonder if they are really remembering, or just unconsciously making it all up.
