As long as no one is forced to use them I don't care. I don't like it so I wouldn't use it. But if some else wants to by all means I wont stop them. But like I said I have a hard time seeing someone wanting to do so voluntarily.
No one will be forced to do anything.
Imagine you have a local government that is being starved of funds and therefore has to cut back on spending. There are local services that are going to be cut to the detriment of the local population and the local economy. As the spending dries up, so does the spending power of the local population, and this can trigger a negative-feedback-loop that can cause the local economy to spiral downwards.
So instead of cutting services/spending, the local govt instead pays workers for 3 days a week in state currency and two in scrip. As the scrip is spent locally, assets are allocated: the worker pays for food off the greencrocer with scrip, he pays the local farmer in scrip etc. and eventually the scrip is paid back to the local govt in taxes or rents. At that point the local government can decide to retire the currency or use it for further projects etc.
This actually works, and has had notable successes over the years, for example:
The village of Schwanenkirchen was confronted with massive unemployment when the local coalmine ceased operations in 1929 as result of the great depression. After two years, Max Hebecker, the owner of the coalmine, got a loan of 40.000 Reichsmark. He used the entire loan to buy Wära stamp scrip from the Wära Exchange Association and subsequently reopened the mine in 1931 (Greco 2001: 64). The miners reluctantly accepted to be paid for in Wära after guarantees that it could be spend at local stores or exchanged for a fixed amount of coal at the mine (Lietaer 1999: 125). Local stores were initially hesitant to accept a new type of currency as well. Nevertheless, the shopkeepers, confronted with the reality that merchandise was consequently bought at shops that did accept the new currency, eventually started to accept the currency too. Additionally, they simply had no choice than to accept Wära as customers didn’t have ordinary currency to spend (Fisher & Cohrssen 1933: Ch IV). With the monthly fee for holding Wära, miners and shopkeepers tried to quickly get rid of their salary. Everyone was eager either to spend or lend the Wära. It means that Wära passed from hand to hand much faster than ordinary Reichsmarks. Secondly, as spending Wära was restricted to local inhabitants and businesses only, Wära remained within the confines of the community. Ironically it was the success of the experiment that also caused its end. In October 1931, the German Government passed a law prohibiting the issuance of stamp scrip. The village of Schwanenkirchen consequently returned to economic stagnation.
There is also another great example from depression-era America but I can't find it right now.
