I'd expect the energy cost of deliveries to be about an order of magnitude less than doing the shopping yourself if you have to drive out of your way to do it.

I'd expect the energy cost of deliveries to be about an order of magnitude less than doing the shopping yourself if you have to drive out of your way to do it. Goods being delivered make up a significant fraction of the weight of a delivery vehicle but a tiny fraction of your car when you're driving to the store, even if you are getting all that stuff.