True. But look at comic books. Sure there are a lot that are still worth a fortune, but after the bubble burst in the early 90s it never really recovered. I remember thinking when I was a kid that I was making an investment for my future kids by buying comic books because the older generation comics were worth so much at the time. These days my comics collection is worth (for the most part) squat.
But I think both of those analagies aren't very good as you don't need any additional hardware to enjoy them. With these games, you need a working system, controllers, and, ideally, a tube tv. I don't think they even make tube tvs anymore.
I'm not a big LD collector, but for what I can tell, that stuff is cheaper than dirt these days though for a long time it was considered superior to everything on the market (arguably even dvds due to the uncompressed nature of the media). Of course hard to find stuff (such as Song of the South) still fetches a crazy price, and Magical Chase probably always will as well. But I wouldn't be surprised if most of the other games drop.
I remember in the mid-90s Military Madness regularly sold on the mailing list for $35-45. Now it can pretty easily be had for half that. Spriggan cost me $70 when it was released. In the mid 90s I remember it fetching closer to $100. Now you can find it for $50. So I don't know.... I guess the market value is whatever 2 or more people are willing to shell out on ebay for it at any given time.
