Are people that nostalgic for their childhoods? Because that's the only reason I can think of for pricing those games for so much. I wonder also if the guy purposely collected them for the sake of a "collection" or actually had time to play everything. That's insane if he had that kind of time to play games.
The insane things is if you read the article on IGN, his reasoning for selling his collection is so that he can buy all of the japanese and european games for the SNES.