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?
Yeah I haven’t done this with a gas nozzle, but I walk off without stuff I need and which I was just holding basically every day, so I will probably manage this feat of incredible stupidity eventually.