I’ve noticed this when shopping for certain things and I don’t like it. But honestly they were a store first and they still own the entire consumer experience. Whenever a third party seller from Amazon contacts me, I am usually surprised because in my mind, I’m buying from Amazon and not from them.

Third party sellers who use FBA in particular are more like suppliers to whom Amazon can outsource part of their job to. In that case I’d say Amazon is a store, with infinite shelf space, and a very permissive policy about letting suppliers stock some of that infinite shelf space themselves sometimes.