I think for some folks living check to check, it's pretty common to not have enough money for a full fill. In the end it's the same amount of gas, so this seem

I think for some folks living check to check, it's pretty common to not have enough money for a full fill. In the end it's the same amount of gas, so this seems like just another one of the myriad ways poor people end up spending more resources than wealthier people because they can't invest a bit more now for better returns later.