Here in the UK, like the US, the self-checkout machines have built-in scales that weigh your produce and calculate the price automatically. There's no extra ta

Here in the UK, like the US, the self-checkout machines have built-in scales that weigh your produce and calculate the price automatically. There's no extra tags involved, you just have to select what the produce is if it doesn't have a barcode. There is indeed an opportunity to "cheat" by weighing something expensive but telling the machine it's something cheap like onions or potatoes. But the machines can be monitored remotely from a security station, so there is a small chance you'd get caught. That keeps most people pretty honest. I'm sure a few cheats do slip though, but the losses from this sort of thing are presumably much less than the savings from employing less checkout staff!