Australia has had self-checkout in supermarkets and larger retailers for nearly 2 decades now.
Usually you will have a single staff member responsible for 4-10 checkouts to override the machine when your product doesn't register a weight, or you move items off the scale too quickly, and it wants them to check it.
It generally just works and is a lot quicker if you're just scanning a few items; surprised it hasn't really taken off in the US.
Most of the issues these days are when they introduce new features like less tolerance on the weight (sometimes adjusting already scanned items trips an error) or auto-scanning fruit and vegetables.
I think the major difference is whether or not the machine weighs the bagging area. When it's not weighing it, you can scan fast and any weirdness is ignored. If it does check the weight, you have to not only deal with wrong weights in the system but also moving anything around or very light items will trip the alert. Generally the nicer the neighborhood, the better chances you'll have finding a non-weighing self-checkout.
I'm not stupid, I know why these measures exist but there's likely a smarter way to let the small things go. Find a way to add percentages to the alerts so that it won't trigger if I rearrange the bags. Factor in the price of an item as well so that it's triggering on meat that doesn't weigh right versus a can of beans.
Usually you will have a single staff member responsible for 4-10 checkouts to override the machine when your product doesn't register a weight, or you move items off the scale too quickly, and it wants them to check it.
It generally just works and is a lot quicker if you're just scanning a few items; surprised it hasn't really taken off in the US.
Most of the issues these days are when they introduce new features like less tolerance on the weight (sometimes adjusting already scanned items trips an error) or auto-scanning fruit and vegetables.