Ruari Again, not sure why you say any loan greater than 30 days is fraudulent?
Anyway, my point about society adopting it's own form of money, when no other form of money exists, shows, at least to me, that the concept of money exists in the brains of people, and the actual things used for money is secondary, to an extent. An important part of that concept is trust. Without trust there can be no money. Which is why when people lose trust or confidence in the monetary authority, then hyperinflation results.
The core problem we have in the monetary world today isn't IMO debt longer than 30 days. It's government spending based on interest bearing loans which are never repaid, those loans just get rolled over continually. Eventually the interest payments on that debt consumes the vast proportion of taxpayers money without anyone other than the politicians and the large banks who provide the loans benefitting.
It's a very destructive cycle because politicians (and society) have taught each other that the way to gain power for any politician is to promise more free stuff to society than the other politicians. This is paid for out of government debt which just keeps accumulating. An example is in the US, interest on debt is soon going to be larger than their defence budget.
The problem then isn't the monetary system, but the political system which has evolved where the way to power for any politician is to promise all sorts of free stuff to the voters - who want that. No-one cares about where the money should come from.
At some point a sovereign debt crisis will emerge, and then the trust issue might be triggered, which will cause an even bigger crisis, where people lose faith in the ability of the authorities to keep the books balanced as it were. So that is IMO the issue that needs fixing urgently.