I understand why people collect sealed games. Rare titles do nothing but slowly go up in value always when sealed over time. Its a good way to ensure you will have items to sell in the future incase you need alot of quick cash.
1) In my experience, most prices plateau at some point, and it's ultimately all about supply and demand. What's popular among vintage game collectors today might not be as popular (or might be even more popular/the same) five or ten years from now. Games are a risky investment, although you are correct in that sealed games hold/appreciate value far better than previously-played games.
2) There is a lot we do not know about the actual lifetime of the game media; the technologies used are far too young to make any kind of absolute assertion about how long a game will work until it will die. Mysterious "bit rot" can one day ruin a game that works today. Most/nearly-all games will likely be ok during our lifetimes, but I often wonder what the "game collector" will be like in distant generations. (I realize that this is only tenuously related to the subject at hand, but I think it's an important point that distinguishes game collecting from more "traditional" types of collecting such as coins, art, "antiques", et. al.)
However games are meant to be played,that other main aspect of collecting sealed stuff, its mostly for pride issues. Seeing the rare stuff sealed on a shelf in a collection room along side the normal opened collectibles, ect... is nice and impressive. Nothing wrong with any of it.
I would say it's lame wankery more than "nice and impressive", but you are certainly entitled to your opinion.
(As I believe I may have said in this thread already,) if a collector wants something that will serve no other purpose other than to please the eye, there are FAR better hobbies to enjoy. And consumerism as an "investment" that will "only" be enjoyed visually (with no other interaction) can be
better enjoyed with things like paintings, photography, sculpture -- or if those aren't your tastes, perhaps you like rare vintage posters, star wars figures, Japanese wood block prints, or some other nerdly hobby or interest you feel neurotic about (in a good way).
No doubt the people who do it feel some kind of happy childhood memories from having these relics from a bygone era in gaming, existing as if they were snatched right out of the 80's or 90's. I've also seen a few collectors whom I believe only want to be envied by other internet nerds, which is truly a petty and hollow pursuit.
Finally, my opinions stem from a belief that videogames, in addition to being an extremely entertaining way to spend time, are sacred and important cultural artifacts. The fact that a sealed-game market even exists means that there is a huge (sometimes exponential) price difference for games I would like to buy. I can not support a hobby that is in direct conflict with mine (collecting and
playing games).
Is this extremism? Probably, but I don't think having sealed games is bad per se -- I have a few, which I plan to open at some point when I play them. Specifically, what I fully believe and support is that "sealed games collectors" are out of their freakin' minds.