So basically you have to manage your own inventory for Amazon, pay Amazon for fulfillment of orders of your product, pay Amazon for storage of your product, and also let Amazon control the pricing to get preference on the buy box. I can see that there may be advantages, but it seems like an awful lot of the burden is shifted to the vendor.

Edit: On second thought, if Amazon has dynamic control of the pricing it may be difficult for the vendors to accurately forecast and stay in-stock.