> since the time I used to spend waiting for the cashier to scan my goods is now spent productively, and usually the lines get shorter, so I can get my groceries quicker, spending less time overall, even if I have to take active part in the process instead of just standing around.

This is 180 degrees from my experience. Whether it's Home Depot, Safeway, Walmart, Target, etc, the self-checkout lines are always longer and take more time.

The thing is constantly beeping at you or telling you to take things off some weight sensor or another.

It barely takes cash that is not fresh out of the mint and the coin slots are filled with gum.

Since the card machines are different tech than the self-scanners, their interface time is measured in minutes, not seconds. I have to tap a nearly endless amount of buttons to get the chip readers to recognize that my card had been in there the whole time, usually re-inserting twice will work.

Trying to find the exact code for my zucchini takes clicking through pages of touchscreen menus. Each time I'm never sure if the screen has registered my touch, so it can take up to 3 taps to go to the next page, or will just jump two pages, each time taking a few seconds. I know, I know, first world problems, but come on, it's super frustrating.

The scale on the things are never up to calibration. So when I put in my own bags, half the time an attendant must come over to clear the warnings. Even when I don't use my own bags, the scales will report errors and cause the whole thing to go into the warning mode, causing an attendant to come over anyways.

When I want to buy beer or cigarettes or cold medicine, I have to scan it in, scan my drivers license in (Passports?! Ha!), wait for it to ping the attendant, wait for them to come over or finish helping everyone else, and then it takes them up to 3 tries to get their codes in and working (usually it does go the first time, though). It takes forever.

The machines are constantly asking for my rewards card info. It's not a real time waster, but the near endless reminders that I have not yet done so are very annoying.

When it's busy, any one of these issues is happening, and the attendants are rushing everywhere. Anyone with the slightest disability is hosed. Have vision problems? Have hearing problems? Have mobility problems? English not your first language? Have memory problems? It'll take forever and it's super frustrating to not just the old lady in the walker, but the whole line of folks just trying to get dinner on the table.

Look, I'm not going to say that a lot of these issues never come up with an actual cashier. They of course, do. But with a person that has keyed in wheatgrass a million times, it does take a lot less time. When the SNAP card is a bit of a hassle, they know what to do. They already know how to get you past all the alerts for the beer and the cold medicine and actually look at a passport. There's a person there to help grandma with her bagging and groceries and out to the car. Where I live, the people are friendly enough and don't set watermelons on my eggs too often.

Personally, via my anecdata, I vastly prefer the cashiers. Now, if I was a teenager buying my first prophylactics or hygiene products, sure, the machines are WAY better. But for me, I prefer the nice smiles and chit-chat to that dumb machine.