NEW YORK ( TheStreet) -- U.S. retailers are bracing themselves for a less-than-stellar year, with consumer spending expected to check in at a rate lower than in 2011. But merchants, online and offline, could be getting a nice shot in the arm from an arcane rule that gives them a bigger slice of the pie from credit card sales. The National Retail Federation says retail industry sales will rise by 3.4% this year, less than the 4.2% expected at this time last year. The NRF points to a mediocre holiday shopping season as a big reason growth is down. Despite widespread agreement among U.S. economists that the economy is improving, consumers haven't gone "all in" on their own household financial forecasts -- they are holding back just enough to vex those economists and U.S. retailers. "What we witnessed during the holiday season is an indication of what we are likely to see in 2013," NRF President Matthew Shay says. "Consumers read troubling economic headlines every day and look at their bottom lines at the end of the month, and they don't like what they see. Pushing fiscal policy decisions down the road will lead to even greater uncertainty, and will continue to impact consumers' desire and ability to spend on discretionary items. The administration and congress need to pursue and enact policies that lead to growth and economic expansion, or it could be another challenging year for retailers and consumers alike." But retailers can still benefit from higher point-of-sale credit card fees -- surcharges put in place after a legal settlement between credit card carriers and U.S. retailers. So-called credit card "checkout fees" could climb as high as 4% of total consumer transactions after a deal between the nation's merchants and big card companies such as MasterCard ( MA) and Visa ( V). In a $7.3 billion settlement, retailers earned the right to charge those checkout fees to compensate for higher card swipe fees from credit card issuers. Previously, credit card firms didn't allow merchants to charge "checkout fees" to credit card consumers. The deal does not affect debit card or cash payments for purchases.