No sense indeed...and that's just the mechanism for the refund. They're also potentially losing sales in the first place. A theoretical example: SuperDuperMan Vol 306 is $100 at Amazon, on sale in June. I pre-order. In April, they lower the price to $80, but I don't have any way of knowing this (unless I personally monitor the prices of all the items I pre-order). In June, the book hits comics shops (a week or two before Amazon). InStockTrades has it for $90. I say, "Cool, $10 cheaper than Amazon!", order it through InStock, and cancel my Amazon order. Amazon loses a sale. I lose $10. InStock wins.