hmm the GoT 4 in 1 does have 4 amazing games on one single disc so maybe for some people they feel that's worth a high pricetag if not just for the sheer curiousity factor. Just like I have all 4 games from their individual japanese releases but if I see it at a reasonable price I wouldn't mind getting the 4 in 1 just to hear Bonk talk hehe
It only has one amazing game. Bomberman is great, but was totally superseded by Bomberman 93 and 94. Bonk is...well, regardless of what you think of Bonk (barely beats Karnonv, IMO) this is a super duper common and cheap game(s) in either region.
Its only high because people are high. A $100 BIN means nothing until someone actually buys it, until then its just a number someone made up.
I seriously question how high this one can really go. It seems like way too many people would already have it, and why would someone who already has it buy another one for a really high price? Even I have this game, and I only have six US releases!
Of course there is the possibility that there are so many people in the US playing on JP systems that there aren't enough 4-in-1s to go around...but why would anyone buy the 4-in-1 unless they are a "collector of US TG-16 games" (ie: a deranged spendaholic) in which case they only have US hardware?
Then of course there are the noobs...damn those noobs. Maybe they just see the game on eBay for $100, assume that's what it should cost, and buy it.