I ran across a website this week that revived of one of my longstanding pet peeves: bankcard interchange fees.

Wait! Before your eyes glass over at the mention of an unglamorous topic you may never have even heard of, please hear me out. Interchange fees are amounts paid by merchants to credit card companies and their member banks when customers pay by debit or credit card. Whether you buy a candy bar at the gas station or a $1000 set of tires, if you pay by bankcard the merchant pays a percentage of that sale for the privilege of accepting payment by plastic.