Trying to understand: WalMart
is logistics, but their logistics customer is
WalMart, and the only way in is to sell
in a WalMart store.
Amazon effectively thinks outside the Big Box, and will let anyone sell anything within the Amazon marketplace. I'm not sure if third-party websites w/ Amazon back-end and fulfillment are a thing, but that's a possibility.
In which case, Amazon effectively sells a marketplace, ordering, and delivery logistics system to its merchandise suppliers.
Maybe. I'm not entirely sure I'm a fan of the "Company X isn't in Market Y, they're actually in Market Z" meme, but it's got utility.
The problems I'm seeing with Amazon now are on two fronts. One is that the actual product review/selection process stinks -- too little control over quality and relevance of what's presented. If I go to a third party, one specialising only in the products of interest to me, I can get a far more appropriate selection of items, and I value that.
The other is morality. Bezos is an asshole and screws people over -- techies, noncompetes, warehouse workers, competitors, and more. I've got a problem with that. I may be in the minority, but that is something which ultimately matters. Perhaps it's the only thing which ultimately matters.