One of the several things that impresses me about this arrangement is that it allows interests people to participate even if they themselves are also facing economic stress. One may not have any spare cash, or even the ability to bid on an item, but if you can at least afford the cost of shipping something out, you can post something for sale. And I'm sure I'm not the only one that has lamented having Too Much Stuff but not being willing to just dumpster things. Setting up a single auction for an item is almost always more effort than the payout is worth what with the need to gather an audience.
Best of all, those of us who can't make a monetary or tangible donation can still participate: in this world where signal to noise is equally challenged by signal to signal, getting the word out is a meaningful contribution itself.