alt Hacker NewsI've tried Amazon for groceries on this line of thinking. Verdict: it's terrible. Their groceries are priced uncompetitively and after a few times having some stranger pick my produce (and doing an offensively bad job of it) I don't do that anymore.
So since I'm 100% definitely going to the grocery store for produce, at minimum, this whole concept fails. May as well pick up the ziploc bags and paper towels as well while I'm there.
The competitive advantage is being able to order in the same shipment as all your other stuff, and it should also obviate the need to go to the store too, saving time and likely money by not being enticed to buy other things while you're there. Even if I didn't use Amazon I'd still use grocery delivery such as what Costco offers for example.