The background to this patent is informative as it helps explain how far reaching Amazon’s thinking could be, and how they plan to keep lowering prices for consumers. One major difference between e-commerce and in-store purchasing is that loss-leading—selling goods cheaper than what they cost—doesn’t work in e-commerce. When customers visit a physical store, they have invested their time to get there so stocking up on additional items is worth it. This doesn’t happen online. So this patent levels the playing field, allowing sellers to offer discounts to online customers based on their investment in time.