[HillRat]

Specifically, Amazon's marketplace subsidizes everything Amazon sells itself. That 15% cut for listing and checkout is a hell of a rentier model, and makes up for their losses in things like warehousing and shipping actual goods. If you want to compete with Amazon as a virtual big box, you're just doubling down on a model that doesn't even work for them.

[dragonwriter]

Of course, maybe your plan is to be like Amazon, and lose money on that model to acquire customers, and then use the customer base to build a profitable marketplace.

I'm somewhat doubtful whether that can work, but its not entirely implausible as a strategy.