[jjgreen]

> Well, can't you at least proxy phones and cards?

Why yes you can, and you get proxy privacy as a result.

The problem is that this information is valuable to the bank and the state, and the only way to keep their nasty little noses out of that trough is not to generate that information, and that means no phone, cash payments. The various technical solutions mentioned in this thread miss the point that the problem itself is not technical, it is sociological and political.

Almost everyone will eventually decide that their privacy is not worth the cost of the loss of their phone. That's their choice, but one should at least recognise that that choice has been made.