I don't know how accurate this theory of mine is since I've done zero research and I'm not an expert on anything, but one could make the argument that one delivery doesn't have the same impact as one individual's trip to the store.

Let's say I take a weekly trip to the store in my car. I also have to park it at the store during my trip, meaning the store must use extra land for parking spaces.

Does the delivery truck drive on that same exact trip for each delivery? No, it's already on a computer-optimized delivery route and it will stop and deliver things to my neighbors.

As far as increased consumption, I wonder how in-store retail tactics compare to online shopping. Sure, I might be tempted by the lack of friction by online purchases, but when you go to the store there are temptations galore. You pass aisles with endcaps of stuff you don't need, you pass the beer and liquor section, and perhaps all the things you want are placed at the back of the store - on purpose, so you pass other items.