>>10499061The fact that they were carded and in secondhand stores probably points to them being closeout stock that never made it to most retailers that were dumped there, which just furthers the point that they were rare--to anyone buying on store shelves at the time.
See, stores would usually load up on an early waves, or wave 1 of a gimmicky refresh wave, at the expense of later waves. So if you were actively looking for them back then, they seemed rare. Even if stock trickled out 5+ years alter..it was 5 years later, the kids and adult collectors had moved on.
As for why they could be found cheap, I guess there just aren't that many collectors for them. Plus its a case where as a huge toyline that was a bestseller, even the rare stuff isn't THAT rare