Do local currencies do any good?

You know, like BerkShares, the local "currency" in Massachusetts.  Tim Harford is skeptical:

True, community currencies may very gently encourage trade with locals
rather than strangers. But the gains from more trade with locals are
more than offset by the losses from less trade with strangers.

See the full post for much more.  I am more positively inclined than is Tim.  First, local currencies blossom when the nominal money supply is too low and wages and prices are sticky downwards.  A boost in the real money supply is needed and the private sector will do it — albeit at high transactions costs — even if the government will not.  That’s why so many of these local currencies blossomed in the 1930s but then disappeared.  They did good but then they were stamped out or ceased to be necessary.

Second, private currencies can serve as a form of price discrimination.  By accepting private currency from your local customers, and indeed only your local customers, you can charge them a lower net price and without being very public about it.  That’s useful if the local economy is in the dumps.  Note that as the local community recovers, this motive for the local currency goes away as well.  It also implies that local currencies will be most popular with merchants who hold excess inventory and have some market power.