I suppose this is a moot point now that everyone just pays at the pump with debit or credit, and it a relic of bygone days of cash money and gas station pump jockeys, but it still bothers me and I have to know:
My uncle and my father always told me not to let the gas pump guy jig-jig the nozzle to get the amount to a round number because the little dribbles of gas you get this way just evaporate and you get nothing for your money. Later they adjusted the advice to tell me not to do that when I am down at the old self-serve and pumping myself.
So - is this true? If there is not a full steam of gasoline coming from the nozzle do you lose some or all of the little dribbles you are paying for? To this day I never bother trying for a round number, I just stop when the nozzle shuts off the first time, but I still wonder.