Counter to this; I work at one of the biggest game publishers in the world, and the assets and source for one of it's most famous games from the mid-90s simply doesn't exist anymore.
I'm not going to say it doesn't happen, discs always seemed to get lost under piles of paper and eventually wind up sitting in a drawer somewhere, only to be thrown out when that persons office is vacated.
Rayman?
Edit: Hmmm... You probably should neither confirm nor deny.