What is invisible to most consumers about Amazon is that they have a massive footprint across the entire supply chain for a wide and growing range of consumer good categories. Brands have been slowly outsourcing various parts of their production processes to Amazon. Amazon manages these parts of the business much more efficiently, and in a more integrated way, than what brands were doing before so it is both attractive and sticky. Many new brands are purely virtual organizations with almost everything built on top of Amazon's ecosystem -- virtual brands were always a thing, but Amazon has made it nearly frictionless.

Because of this, I expect them to make a ton of money off consumer retail even if their marketplace fades into the background. The brand management business on Amazon has been growing like crazy too, which pretty much assures Amazon will always be taking their dollar.