They do have a weakness - Search.
There are a trillion products in a trillion categories and some meaningless small number get displayed on the first search result page. This is obviously highly abnormal and their own search teams will tell you that.
It creates unmonitorable arms races, unnatural uniformity across myriad cultures and thought processes, pissed sellers, frustrated customers and just bubbling tensions of all kinds.
It's like taking all the animals and plants in the world throwing them on an island and telling visitors they experience everything through a magic window, but 10 at a time. Ofcourse they cant. If you know what you want to see - great! If not its just a useless experience.