A 30 per cent rise in fuel theft has led to a new government crackdown. But what happens if you're caught short at the pumps?
Isn't it embarrassing when you get to the shop checkout only to realise that you've left your purse or wallet at home and can't pay?
At least in that situation you can put the goods back and make a swift, if red-faced, exit.
But what if you've just filled up your car with petrol? Giving it back isn't an option, so what happens?
Caught short at the petrol pump
Kim, 27, a PR executive from York, has first-hand experience of this.
"I filled up my car at Morrisons but when I went to pay I entered the wrong PIN number a few times and the cashier told me my card had been declined.
"I didn't have any other method of payment so they asked me to fill out a form giving my name, address and other details and come back later to settle up.
"I did so straight away and was given a receipt to show I'd paid."
Kim's experience was down to a genuine mistake, and filling in a "no means of payment" form is standard procedure if you fill up then find, for whatever reason, you've no money to pay.
'Alarming rise' in fuel theft
But according to Brian Madderson, chairman of the Petrol Retailers' Association (PRA), deliberate fuel theft is on the increase.
"PRA members have reported an alarming increase in the 'no means of payment' system being abused and in 'drive-offs', where the motorist fills their tank and leaves without paying.
The British Oil Security Syndicate (BOSS) is an independent association which campaigns to reduce crime on petrol station forecourts.
It estimates that £4.2 million was lost from drivers claiming no means of payment but failing to return to pay last year.
With a further £20.4 million lost from drive-offs in 2012 - a rise of 30 per cent on 2010 - the combined loss though fuel theft for the average UK service station last year was £2,860.
New crackdown on fuel theft
Motorists who repeatedly fill up without any intention of paying, are now going to be dealt with under new Crown Prosecution Service (CPS) guidelines.
Kevin Eastwood, executive director of BOSS, explains: "If someone fills up then realises they don't have the money on them they are asked to complete a '"no means of payment" form.
"This acknowledges the debt and promises to pay within seven days.
If payment isn't made their details are passed to a debt collection agency and that could lead to action through the civil courts.'
Motorists abusing the system
"However, some motorists have abused the system, repeatedly filling up without any intention of paying it back.
"In the past the guidelines for dealing with this situation were unclear - some police forces prosecuted this as fraud whilst others didn't."
But, Eastwood explains, new Crown Prosecution Service (CPS) recommends prosecutions if a motorist can be shown to have repeatedly filled up claiming to have no means of payment.
He adds: "Additionally, motorists who provide false details to a fuel station will also be prosecuted."
"And if someone fills up and deliberately drives off without paying, that is considered theft by the police and will be pursued as such."
Two or three 'drive-offs' a day
Collette Bates, manager at a Texaco petrol station in Sheffield, has experienced both forms of theft.
"Sometimes people make a genuine mistake, are very apologetic and pay promptly afterwards.
"Others you can tell are going to fill in the form and disappear. But we pass on the details to a debt collection agency who chase them up.
"We used to have two or three 'drive-offs' a day.
"Contacting the police and using CCTV footage didn't help as usually the thieves used cars with false number plates.
"Sometimes you'd see the same guy doing it over and over, and he'd smirk at you as he drove away."
Security spikes 'effective deterrent'
But now those thefts are a thing of the past, Bates says. "We have had security spikes installed, which rise up out of the forecourt.
"These can be activated by the cashier if a motorist tries to drive off without paying, and they will instantly deflate the tyres.
"We've got warning signs up about the spikes and they have proved a very good deterrent as there hasn't been a drive-off since."
Fuel price calculator
Petrol and diesel costs remain high. Luckily, we've come up with a handy fuel price calculator so you can work out the cost of filling up your motor.
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