To be clearer: that people would give away 10k of them to buy a pizza indicates back then they were seen as essentially worthless, meaning you'd probably not take much care to preserve the ones you mined for a while while playing with the software you wrote.

A lost key would explain it. Maybe that was your point.

If money didn’t move, that may be because the owner didn’t want it to move, or because they couldn’t move it bascule they lost the access key.

From an outsider’s perspective, both look 100% identical.