I had the same thought process. One point to note is that a delivery guy might deliver to multiple people in your neighbourhood, so his driving is amortised ov

I had the same thought process. One point to note is that a delivery guy might deliver to multiple people in your neighbourhood, so his driving is amortised over those orders, whereas when you drive the shops you're making the whole journey for yourself. If delivery was organised extremely efficiently, e.g. a single delivery service that delivers everything at the same time as the post, it's no doubt that it would be much more efficient than individuals going to the shops themselves. So we're on a spectrum where the extremes are "much better" and "much worse" than pre-internet, but it's not clear to me where we are on the spectrum; in particular, it would be interesting to know whether the net energy consumption has increased or dropped.