Grocery delivery is not the same as grocery shoppers. For me, the two largest local grocery chains are offering grocery delivery and/or pickup, which always bypasses the shelves - IIRC one of them has the shelf-stocking people pack the deliveries before they go onto shelves; the other is packing the deliveries in the logistics centres alongside with the stuff that goes to restock the many smaller stores.

Obviously, having someone go to a store just for your purchase and walk along all the isles to pick stuff up is horrendously inefficient.

> bypasses the shelves

It's obviously inefficient to send someone to a store to grab stuff, but "giant room with products on shelves" is a pretty efficient setup. They can do some of it in the back room, or a warehouse full of pallets, but to a large extent companies end up building "dark stores" that are almost the same as a normal store, but with no customers allowed in.

To a large extent store chains already have them, that's the (few) logistics/distribution centres out of which they supply the (many) stores. The store shelf is essentially just a short-term cache.

Are the preexisting logistics centers designed around picking up single items off the shelves? I would have expected them to be set up around bigger blocks of product.

The preexisting logistics centers are designed to take a pallet of item X and allocate different amounts of it to different boxes each going to a different smallish shop; doing so in an multi-hour cycle (2-3 times a day?) to ensure that every type of product is distributed along these boxes. During this process they also put part of the product not in "delivery truck going to shop A" but to "delivery truck going to home deliveries". It does need some ripping of bigger blocks of procuct and repackaging to bags, but it happens at the same time as they're ripping even bigger blocks of product for supplying stores and shelves.

But the essential difference is the "push vs pull" - instead of one delivery pulling items from everywhere (which is a new process that grocery chains did not have) you have the supply process pushing items to many delivery targets, which is a process that grocery chains already have and have optimized.

Or just ordering from the supermarket directly, for those that provide such a service!

But you run into the same issues mostly because Kroger's delivery service is "just as 3rd-party" as Instacart. It's still an employee going through your store, grabbing stuff off the shelves and delivering them to you. There's basically zero first-party advantage.

Yeah, this is exactly what it was. We used a Kroger store because they had a much better selection than Safeway and in the end didn't really get what we wanted. At the time I had guessed it was because the 3rd-party picker didn't know where some of the items were and didn't have time to go looking for them.

At least the in-house grocers are more familiar with the layout and product offerings. From a process perspective, couldn't supermarkets process the delivery orders during stocking?

Having been warned about Instacart I made a point of doing just that, only to have the grocery store run the order through them anyway. The whole experience felt fraudulent, from the bait-and-switch between service providers to the bait-and-switch from carefully chosen sale items to expensive and inappropriate "substitutes". Reportedly at least Instacart proper has a feedback mechanism. With the white labeled service you're out of luck.