In reply to Jim Walton:
The pleasure of owning them. If you've got the space to put them out and get a warm fuzzy feeling when you look at them and you read them from time to time, then keep them.
If they're just gathering dust and don't get touched from one years end to the next, then get rid of them. If it were me, I'd keep them tho.
I have a small collection of comics, which are currently in the loft. I hope to get them out on the shelves soon enough, but my wifes book buying habit keeps the shelves full.