There is not room for a big box in every neighbourhood, not even one, let alone the "standard collection" of Costco/Home Depot/Wal Mart/Barnes and Noble/Dept. Store/etc. Plus add Amazon and the like.

Home delivery is much more labour and truck intensive on the part of delivery company, and for many requires they be home to receive it. At one home I've had, it's not a problem, the area is very safe and they just leave stuff by the door, no signature. However, if they do require a signature as they sometimes do it's a royal pain when I'm not there, and stuff is delayed another day. At another house, leaving valuables by the door is not so workable. And this is for delivery that takes at least 1 day (at high cost) but usually several more. I'm talking about delivery in 2-3 hours, not 2-3 days.

The realization is that walking to local shopping is good. Leaving out the benefit to the environment, traffic and your health, walking to a local depot 1500' away is about 6 minutes, which is faster than a typical car trip to a shopping center. I started realizing this when I had a place with a tiny but nicely stocked set of stores within about 600' -- it's really a lot better by a longshot than the typical suburban arrangement, though shopping centers have more selection and better prices which is how they manage to win.

Sharing a warehouse complex is no big deal, they companies all share delivery companies, and in this case the warehouse system is the delivery system.