(that said if I have a lot of produce the human cashier is faster)
Surely all of the upsides of self-checkout have a higher weight than the machine beeping at you.
Also, they beep because your attention is spent rotating each product to let the scanner find the barcode, and you might not notice that it scanned otherwise, and accidental multiple scans cost the customer money.
Like everything in capitalism it is just a strategy - if shrinkage or other issues are more of a concern they would keep it behind the counter like jewelry stores or if people reacted negatively enough it would fail.
The faster I can be out of there, the happier I am. And, less labor spent on scanning items means the store can be open for longer hours, have more organized shelves and be cleaner, etc. All in all, this is automation that increases the efficiency of the operation. Yes, you pay some cost in that you have to place your items into bags (with the current iteration of the technology) but I think you the customer get something out of that work, even if it's just a slightly lower rate of price increases.
It is time to think seriously about how we are going to deal with fewer jobs available. Will the increased corporate profits that result be spent on giving cashiers education to become knowledge workers to further increase these profits and the efficiency of society? Will the money be fed into basic income or public services, so that everyone in society will be taken care of even if there are no low-skill jobs for them to do? We are already seeing what happens when we don't think about these things in certain industries, and it's not great. Someone will have to step up and say, we will be the country that takes care of everyone, because the "work 8 hours a day and you get a house" era is long over.
> Opinions may vary about the convenience, efficiency or "upsides" of that
I highly doubt that the savings on labor cost will translate to "longer open hours, more organized shelves and cleaner, etc", I would guess the savings translate to more profit and more concentration of wealth at the top.
Look, I'm not so much of a luddite that I _refuse_ to use self-checkout lines, I'm just realistic about what the motivations are: maximizing profit.
Also, the number of labor required stays the same, just now it's unpaid labor.