Love the idea,but how do you handle support,customer-shopper arbitration(either side claiming the delivery did or did not happen for example),really bad customers/shoppers (basically quality) without central management?

Another solution would be to have a separate pickup location where shoppers drop it off at that location and customers would pick it up at a different date. This helps people that want the convenience but also it helps eliminate "food deserts". If say whole foods is 10miles away,the grocery is delivered 5 milea away, that means people that consider 10 miles too far can now pick it up at a closer location. I think this whole idea has potential at a larger scale, I would love to order stuff from amazon or ebay and have it delivered at someone else's house where I can pick it up later -- one more layer of privacy if I use gift cards and the like to shop they will never need to know my name,phone and address directly. Storage providers can charge by the hour/minute.