Shelle - excellent that the councils have an incentive!
Yesterday I wrote to 10 large shopping chains letting them know about the cornstarch bags & included a sample (reluctantly, mind! I like my bags) - I wonder what response I'll get !
Well, the response so far from the supermarkets that I wrote to is that it is about 80% more expensive to use an alternative to whatever they currently use in their bags, so they won't be replacing them. So it really is a matter of encouraging everyone no to use them - and to continue to lead by example.
(just got back from France where no free plastic bags were offered at the checkou of the local supermarket, just the heavier/thicker re-use ones for sale)