Ok now I am curious where you live that you have to provide ID to shop. Here in the US we scan the items and then swipe our payment card, the ID is only used to check your age for tobacco and alcohol purchases which can’t be sold to minors. An employee has to come look at the ID to make sure a minor hasn’t borrowed someone else’s, so it doesn’t even get scanned. Employees just swipe their work badge and confirm that they checked your age.

As for the pain, a lot of self checkout systems have very limited space and can be awkward to run all your items through. Manned stations have the conveyor so you can unload multiple items from your cart at a time to be scanned. They also have more end space so you can have room to bag everything if you are doing a big shopping trip.