The "plebs" will develop a new currency of their own. And by this I basically mean anything from bottle caps to IOU notes etc. Monopoly money, whatever. Arguably they could use something actually valuable too but using an IOU-type thing kinda secures it against theft. Point is that it starts with small communities with some degree of trust of course. Alternatively, trade work for food and goods - but we're primed to use money so I think we're likely to just create a new currency since we already know it's simpler to just trade 5 bottle caps for a carrot than it is to wash dishes for... oh i dunno, 3 carrots or whatever.
This kinda is what we should be getting to do anyway at this point. The 1% should be regarded as a force of nature. You can't win against them anymore you can win against a volcano. Best you can do is work around them (instead of trying to beat them at their own game which they are constantly rigging in their favor anyway).
Money itself only has as much value as we give it.