People I've heard from say that they never get around to playing the games, but they buy them in bundles like this because they can get a bunch of games cheap, and maybe someday they'll have a chance to sit down and play them.
Like a Baseball card. You buy them up when you have some extra money, or got them as a gift, and you store them away, maybe someday they'll have value. Right now, their only value is that they are in your collection at all. (Pokemon/Magic/Whatever)
I'm an indie game developer myself, and it's interesting to me because it seems like people have become accustom to buying games because they heard about them instead of because they want to PLAY them. I'm totally guilt of this myself. I've spent many bucks myself on iOS titles just because of the hype, play them once, and that's it. Most times I feel like a real sucker for falling for it. Rarely do I get a gem.
I'm usually the edge-case for stuff like this, don't really expect anyone to agree :)