1. I am located at LA, have a friend at New York who has something that he needs to give me.
2. A person named Adam is on his way back to New York to LA.
3. Why not let Adam take that something from my friend in New York and bring it back to LA with him?
4. Waiting/paying for USPS, UPS, Fedex, is too long and costly. This is better
On the other hand, whenever you get such a large megacorp involved, there are certain inefficiencies inherent to being a large megacorp... e.g. I remain price competitive with amazon, so I could be wrong.
Really, I think the food idea is great because it's filling a need that isn't being filled at all. As far as I can tell, delivery services are pretty dang good. you can get something light shipped across the country in a day or two for ten or twenty bucks. Seems like a good deal to me. Food on the other hand, other than pizza, where I am, I can't get food delivered until I'm at 'catering scale' (water.com doesn't work for just me and my employee, unless I want to pick up myself, which defeats the point)
The thing is, I'm in the heart of silicon valley. Lots of overpaid nerds who don't want to leave the house (or office) - we'd be glad to pay even taxi per-mile rates to get someone to bring us our take-out.
There are more underpaid kids around here than you'd think, people who would be happy to make food runs for less than taxi per-mile rates.
Figure out how to hook up those two groups, and you have a business model.