Near the end of this episode Billy asks his sisters for pennies for gas to run the stove. At this time (and even decades later!) it was common for homes to have gas and electric meters for prepaid service. These meters took pennies or shillings, and later on other coin denominations. The collection boxes could become so full that families waited in anticipation for the meter reader to empty them, because otherwise space could run out leaving the occupant with no way to access electricity or gas. People sometimes cheated by using washers or other shaped material--even ice--in lieu of a coin.