I can only talk about our (Postmates) experience but having multiple pickup and drop-off locations increases the efficiency of a fleet dramatically. In larger cities like New York, LA, etc. multiple warehouses are a huge advantage. Off course i'm mostly referring to on-demand or same day deliveries here.

Maybe i should add some more color here. If you think in terms of traditional delivery, one warehouse is enough. But i'm not sure that this paradigm (one van drives to a warehouse, collects a bunch of stuff and delivers it), is what works best for on-demand, 2-hour or same day deliveries. Multiple, fast and easy to reach pickup locations are an advantage at scale. Especially for deliveries where minutes matter.

Ultimately, we will probably see a combination of both.