I blame Sony and the PS2, thats where retro collecting began for me, I never had a ps1 and now i could play some of the games id read about, this led to the thought "well, if im going to play ps1 games, i may as well play them on a ps1", im sure this was true for a lot of other people too, also around this time emulators were just getting to the point of good compatability/accuracy, so a lot of people played games theyd never even heard of before, then of course the Wii came along with its virtual console and things really took off!
I hope its just a fad, maybe when its no longer "cool" to be a "nerd" lots of these people will get out of the collecting game...