At contemporary prices, it makes no sense to purchase gasoline at the pump in fractions of a penny. This seems like an antiquated reference back to when the price of a gallon of gasoline was in cents, not dollars.
15 gallons of gas at $3.759 would cost $56.385. How does one pay for that half cent?
15 gallons of gas at $3.76 would cost $56.40, which is much easier to understand.