Those are excellent points that I had not considered (or even been aware of). Still, though, while the set of brands and products available at a brick-and-mort

Those are excellent points that I had not considered (or even been aware of). Still, though, while the set of brands and products available at a brick-and-mortar store is predetermined in a way that the customer has little to no influence over, it's at least much more visible if I go into Kroger one week and there's a full selection of different brands of mac & cheese, and then come back the next week and it's all Kroger brand with no sign of any other brand; whereas if I go to Amazon and search for, say, AA batteries, or Lightning cables, and all I see is AmazonBasics batteries and AmazonBasics Lightning cables, is that because Amazon stopped stocking Energizer batteries and Anker cables entirely, or because Amazon forced them to a later page of results to bolster sales of the AmazonBasics brand?