For the context of the article, pay at pump would not prevent thefts due to drawing fuel and driving off, nor from people who draw fuel before pay day then tell
the staff that they “can’t pay today”
As he mentioned in the article, it would annoy honest customers if they had compulsory pay at pump, and he would lose business to other garages (hence the “industry would have to adopt it”)
Pay at pump secures some funds against your account, and the banking system does not instantly release that when the actual charge is made. That can leave people short of funds when they really do have it in the account
e.g. they have £150 in the account, pre-pay secures £99, they take £30. That locks access to £129, and their available balance is £21 instead of £120 -
perhaps for a few days
Or they prefer to pay cash - do they have to leave cash at the counter?
An inconvenience is that if you want to fill from almost empty then the pre-authorised amount will probably not allow a fill for all but the smaller ranges of cars