[rdl]

New York is probably even stronger than the Bay Area for this kind of service, but there are entrenched competitors there.

College campuses, big industrial parks, and maybe military bases would be my next pick after NYC and SFBA. Another interesting market might be events -- during Sturgis, or Oshkosh, or other vents, running something like Instacart would work, while it wouldn't work in the same towns otherwise.