Unattended stand; no cameras nor security guards
If you take a break from the city and go into the suburbs, often times you can see these kinds of unattended vegetable/fruit stands near farms. You can see what are sold and the price for each product. There’s a box where you put your money in for your purchased goods, and sometimes they even have a plastic bag to put your vegetables in. If you need changes, you simply take the necessary amount from the box.
The stand is unattended; literally there are no vendors around. There’s not even a security camera.
Of course people can “steal” if they want to; nobody’s watching you. Yet the Japanese are known for their fidelity from way back, and the customers sum the total in their heads, place the money in the box, and go on their way with their purchase.
It’s hard to imagine something like this really exists in this world still, but whenever tsunamis or huge earthquakes or some giant calamity put the people in a crunch, they never riot, crashing the doors of grocery stores and plunder. The same thing can be said in these unattended small “shops,” where EVERYONE pays full price for what they have purchased, even not being watched.