This actually sounds like a fantastic service that the publishers could offer if they were progressive enough.
How about a startup? Of all people in a position to implement the physical side of this: Half Price Books. They could scan the UPC barcodes and see what books are in a catalog, then offer to give the customer an eBook for a nominal fee. So they would be receiving money instead of paying it out. This would be a way of publishers to be able to make money off of IP with sales that have already dropped off. The publishers would still have to cooperate.