The margin ferry is not coming not ever. If they fully optimize all of their warehouses it won't make a difference. They do not operate as efficiently as other retail organizations. 15 years of data proves this.
Wall street and you nem think that because AMZN doesn't have to maintain store fronts with employees that they should have significantly better margins right! But the cost of maintaining data centers, fulfilemnt centers, shipping, advertising, and search engine optimization as it turns out is more costy than a traditional retailer.
Demand will be destroyed if they increase the price of goods/services and Bezos knows he has to continue to subsidize his growth to maintain his stock price.