This is one of those obvious things that I don’t know why others haven’t commented on it. I recently bought a collection of Medeival Troubadour Songs conducted by Thomas Binkley. It was one of the rare occasions where I paid retail. Amazon promises a date for your shipment to arrive. On your “check order status” page, it gives you an option for contacting them if the order is late. I contacted them a day after the due date, and they wrote me back, agreeing to waive all shipping costs.
This is just basic sense for customer service (and I applaud Amazon for doing it). It may be a way to get some compensation for inconvenience in a tangible way.