People don't usually drive to the store every single day for a single item, whereas amazon would deliver a single item to people every single day.

That same delivery vehicle can service 100s of homes at once though, which is why it's more efficient regardless of 1-day delivery windows.

I'm sure they could do a better job of batching deliveries for a single drop off per day but I don't think that's as bad as it might seem considering the overall reduction in consumer-to-store travel.

It's more like, instead of you and each of your neighbors driving to the store separately, you're driving to the store alone and getting groceries for yourself and all your neighbors at the same time.

Maybe it wouldn't be so bad it there wasn't such a hurry. It's the next day or possible this day delivery that makes this so bad.

When people go shopping it's same day too, no matter how small or trivial the item is.

Quite the opposite, people usually don't actually go out shopping just for a single trivial item, they delay the purchase until some later time when they go shopping for some important item or many trivial items at once.

Splitting the same total purchases in many separate "shoppings" is the fragmentation problem that causes much more "delivery events".

I find plenty of instances of people buying 1 thing at a store so it goes both ways. Regardless, the marginal cost of adding an extra stop to an optimized delivery route is very low compared to a shopping roundtrip for a single consumer.

people usually don't go shopping every day possibly multiple times a day. Whereas Amazon gives them the ability to order things such that a car drives up to their house and delivers stuff multiple times per day.