John, the fee difference with a debit card depends on how you use it. If you use the PIN, then the fee is much smaller that if you use it AS a credit card (that is, sign for it).
It doesn't affect what they take out of your bank. In your example, they'd take $200 if you used debit w/PIN, debit by signing, check, or you could give them cash.
The difference is in how much they get from the bank. They get $200 if cash, generally $200 if check, I'd estimate $198-199 with debit/pin, and $193-195 with debit/sign (or credit/sign).
So, the less they actually get from the customer, the more they charge. Arco gives a cash discount, and if you use a POS card, they'll nick you for 25 cents for the transaction but give you the cash price. But use credit (or signed debit) then you pay 4 to 6 cents per gallon more.
They are practically the only business in the US that passes the transaction cost to the customer. At least they used to -- I rarely go there.
Note: your bank may also charge you a fee for debit. This is just an extra fee to fund those 10 million dollar bonus checks. |