The distributor provides a single address that content re-sellers converge on and feed off. Network effects mean that content brokers have to invest much less in marketing, branding and advertising once a product's first mover advantage is established. The pie is getting bigger. As this tectonic shift reverberates through the whole distribution chain, retail outlets are beginning to transact directly with content creators. The borders between the types of intermediaries are blurred.
Many publishers have virtual storefronts.
Many authors sell directly to their readers, acting as publishers. Intermediation is not gone. It is here to stay because it is sorely needed. But it is in a state of flux. Old maxims break down.