How many of those copies of MC that you see on eBay are being sold by the Electronics Botique or Toys R Us that originally stocked them in 1992? I'm going to go with "zero", meaning that every single copy of MC sold on eBay, or anywhere else, is being re-sold...and probably not by the original owner. These things are probably mostly 3rd or 4th hand at this point.
And when the value goes way down...they'll change hands again. When MC is selling for $50 on eBay, these guys will lose interest in owning it. The exclusivity is all they wanted anyway, not the game.
Seriously, this crap happens all the time with all sorts of stuff. People used to pay hundreds of dollars for certain Magic and Pokemon cards. Remember Beenie Babies? Superman #75? The 1990 Mercedes S class?
People went apeshit over all this stuff, but where is all that crap now? I don't even know because nobody gives a shit.
Only the really great stuff holds its value over time, and Magical Chase...its nice, but its no low numbered White Album or 250 GTO. Its just a friggn game, and they made thousands of copies of it.