Hi
@anand , it's a bit of an "in joke"
Some 4wd enthusiasts here prefer to line up at the "hi-flow" diesel pump with the big trucks, B-doubles and road trains in their Nissan Patrol or Land Cruiser (mainly). Whereas the big boys might load up to 1000+ litres (200+ gallons) , our intrepid 4wd pilots probably take on a tenth of that amount. They may save 2c a litre and two minutes filling time.. but hey...
My former neighbour, a fuel bowser tech. used chuckle at this saying any perceived gains were illusory since the margin for delivery error on a high flow pump was slightly greater than a slower pump.. wasn't intentional but related to the flow measurement tech. at the time. Perhaps it has improved. perhaps not...