its only useful for company/govt vehicle fleets.
what they do right now is that they give you a card and you can get any car filled and ur company will pay for it.
(leading to mis-use of the facility)
some companies give a car specific (model / number plate) filling card. so that u can only get petrol in the company car.
finally some companies just re-imburse the fuel expenses based on the receipts.
using this, no need for the card/receipts.. u just go to the petrol station, get it filled and off you go. the company will be billed automatically. moreover, the mielage is also read so that they have an idea that ur not taking the fuel out of the car after getting it filled:P