The same reason someone is willing to pay $119.9 million on an original Edvard Munch "The Scream" painting. It's a collectible; a show piece.
As far as you other gems, who says I stopped posting? I just posted a couple days ago about my MtG find. The reason I declined your offer is because it simply was not worth the effort. You're offering me a hair over $3 a game. I can get at least half that amount on Serpent Isle alone. As it stands, the floppy based games probably don't work. They are literally just collectors items. If you want to buy a bunch of the common CD-based games at $5 a piece plus the cost of shipping, I'd be fine with that.