That is not at all what drop shipping is.

  Drop shipping is a supply chain management method in which the retailer does not keep goods in stock but instead transfers customer orders and shipment details to either the manufacturer, another retailer, or a wholesaler, who then ships the goods directly to the customer

It's not possible that today's buyers are having them shipped to their own customers? Maybe somebody set up preorders with bots to hit Amazon to fill the orders. Or found a way in Amazon's system to reserve the item but delay shipping until they get the destination address and collect their markup.

^ Precisely. Drop shippers are the ones who have the infrastructure set up to pull this off, and would have started selling early to capture pre-sales.