In the USA, the self checkout line is easily 5x faster than the human line. Cities are growing, but the size or number of grocery stores is not.

This is only true because of having to wait in line for the checkout personnel. Once you get to the person, if they're even reasonably skilled, they can check out your groceries faster than you can.

My local grocery store has something like 15 checkout aisles, and usually only have one or two open. If they manned each aisle, there would be no wait and self checkout would be pointless. But they are not going to staff properly because the CEO needs another yacht.

In Germany, the entire self-checkout section moves as fast as one human cashier (they're very skilled, this is no joke). And they have one human supervising it at all times. And it takes the space of two human cashier lines, so they double up one of the other lanes. At the end nothing is really gained except a little bit of privacy (but not really because the supervisor's terminal still shows everything you scan)

> worker shortage is the main reason why self-checkout became popular here in Europe at least

What exactly do you mean?

That the companies moved to self checkout because they couldn't get the staff?

Or people prefer self checkout because the manned tills are few in number?

The first is very very hard to believe

>The first is very very hard to believe

Why?

At least in the US our unemployment rates have been very low. Higher demand for labor leads to higher labor costs which allows more expensive automation to be economical.

You can say "Well pay them more", but that doesn't get you out of a labor shortage. That just ensures you get the labor rather than someone else.