You drove and pulled up to the gas station to fill your gas tank. You exited your vehicle, opened your gas tank cover, grabbed and put the dispenser nozzle in. You also had to pay at some point.
How can you forget that the hose is still connected to your car when you drive off?
In the UK, petrol stations almost always have CCTV monitoring pumps, and can use number plates to identify anyone who leaves without paying. Probably similar in the EU I would think.
That said, it’s also increasingly common to have a pay at the pump system, where you have to use your credit/debit card before you can fill up, with the amount being taken off automatically based on how much fuel you used.
How did it work before automated monitoring?
What’s to stop someone driving cross-country or even just for a 1-off fill up and wearing a hat and glasses and covering their plates with cardboard and tape right before coming and going?
E: someone else in the thread mentioned an attendant will make sure they can see people’s faces before starting the pump