Historically, all margin uplift has come from AWS and advertising, but their financials seem to show they are struggling to keep their e-commerce reinvestments in line Analyst's Disclosure:I/we have no stock, option or similar derivative position in any of the companies mentioned, and no plans to initiate any such positions within the next 72 hours. I wrote this article myself, and it expresses my own opinions. I am not receiving compensation for it (other than from Seeking Alpha). I have no business relati ...