I agree with you that AMZN is a well run company and provide important services. To me, shorting a stock is a reflection of the perceived too high a valuation of the company rather than how well its run or its relative importance. Mr. Bezos rolls most/all of the earnings back into the company by adding more services/value which is great long term but that leaves profit margins in the low single digits and a p/e of 188 as +Rohit Jenveja
mentioned. Unless you have a 20 year investment horizon on AMZN, like Mr. Bezos has, you're return on investment might not be worth the risk. At some point AMZN will get so big, it'll hit the same "law of large numbers" penalty box that Wall St put AAPL in and the p/e will adjust accordingly. Again, its not AMZN (or AAPL, which I think are both great companies), but Wall St's perception, right or wrong. Unfortunately, they have the big ($$) stick and can move the stock price at will (illogically it seems at times).