I think that the government did cut the maximum rates banks could charge merchants on their cards. They felt that the banks were being abusive.
"the Wall Street Reform and Consumer Protection Act. It is known as Dodd-Frank, after the two Democratic legislators who pushed it through: Massachusetts Rep. Barney Frank and former Connecticut Sen. Christopher Dodd.
Provisions included a fix-it job engineered by Illinois Sen. Dick Durbin at the request of major retailers like Walmart, who had their own beef with banks over debit card fees. Durbin's solution ordered a break for the merchants and wound up shifting the cost to the debit card-using public.
Some consumer protection.
When debit cards came into use, banks charged retailers a flat rate to process sales. Over time, they shifted to taking a tiny percentage of each sale, with the average fee in 2009 working out to 44 cents per transaction.
Because processing cost only 4 cents per sale, retailers felt victimized. Dodd, Frank, Durbin and colleagues came to the rescue by ordering the Federal Reserve to figure out a fair price.
The Fed settled on a 21-cent limit that can grow to 23 cents in some circumstances, one result being that banks are suddenly losing $6.6 billion in annual revenue."http://articles.nydailynews.com/2011-10-02/news/30252272_1_debit-card-fees-retailers
So instead of charging 1100% markup they are only aloud to charge a 575% markup. Banks like to use the new reduced fees as an excuse but I think it has more to do with all of their bad loans.