Gas stations should not be able to tack on an additional charge per gallon for credit card use. The charge they incur is on the TOTAL sale, not per gallon
Why is this important?
Gas stations are charging upwards of fifteen cents and in some cases a dollar more per gallon for the use of a credit or debit card. This should be a "cost of doing business" or a they should charge a small percentage of the TOTAL sale not per gallon.