someone bought those machines in liquidation, whether they want them or not, or even know if they're theirs

It's a risk to remove the machine and do something with it if whoever that is eventually says "give those the fuck back to me I wanna sell em to nerds who'll use em for their collections" or whatever

Companies doing the bankruptcy that redbox is going through are required to liquidate their assets. The machines have been or will be sold. And you can be sure there's an inventory.