On Sat., Oct. 1, new regulations from the Dodd-Frank financial overhaul go into effect on debit cards. Specifically, they impose price controls on “interchange fees,” the fees that banks and credit unions charge to retailers on debit card transactions. The average interchange fee is about 44 cents. The new rules limit the fees to 21 to 24 cents. “The costs of processing debit card transactions doesn’t go away because you limit the price,” said John Berlau, director of the Center for Investors and Entrepreneurs at the libertarian Competitive Enterprise Institute. “That shifts the costs to consumers.”