If Microsoft can get hammered for packaging Internet Explorer with Windows (and probably rightly so, given the market conditions at the time), there is a direct analogy to be made here.
Pick what you want to be: if you want to be the greatest goods index and shipment company in the world, fantastic. But you have to accept that you cannot sneak some of your own other-products to the top using that power. In this case, spin off your Kindle etc companies or have them broken up.