I live in San Francisco, and I think these delivery services are great for all the things I do not enjoy buying: soap, paper towels, socks, bicycle pump. Having those things delivered gives me more time to peruse the cheese shop, the farmer's market, the butcher shop, and the bakery. Also sometimes, like holidays, I find I need some ingredient and it's better to have it delivered than to quiesce all my cooking activity, roundtrip to the store, and resume without breaking my timeline.