When talking about unemployment, I think people focus on wrong aspect. Replacing people with machines is good, that's why we make them. The problem is with how our society functions. Rather than less work for same pay, we get unemployment as a problem.
As for machines, I hate their weight checking. Sometimes it just needs me picking up the item and slamming it onto the bagging area. In the past, some of them used to show weight difference from expected weight, so I would be able to figure out what to shuffle around.
There's also issues with permissions. For example, removing items or completely exiting shopping requires employee permission. What for?
Also, recently 2 shops decided to change the UI. In the past, you could type in number of items if you had multiple, especially useful for pastry. The new UI requires repeatedly pressing +/- buttons. Really nice when you have 15 of something.
Lastly, scanner cooldown. They seem to have a large cooldown. I just want to quickly scan the items, but no, gotta wait 2 seconds between each item.
The only places where it's a bliss are supermarkets with systems like scan&shop. You take a portable scanner and scan everything as you put it into a cart, then just pay at the end in a few seconds.