Great just-so story. Here's a completely opposite one: Every last online retailer would use shopping carts apps of the highest quality if Amazon didn't have s

Great just-so story. Here's a completely opposite one: Every last online retailer would use shopping carts apps of the highest quality if Amazon didn't have such a huge market share. But the shopping cart developers saw the writing on the wall of an encroaching amazon and got out. If they hadn't, everyone who wanted to sell something online would have easy access to a multitude of of hosting platforms explicitly target merchants. And because they're in competition with eachother, the quaility of their platforms in this hypothetical is better than IRL-Amazon's local maximum.