Money for Nothing and your (bonus) checks for free

Nouriel Roubini's hue and cry to nationalize the banks last winter proved to be overwrought. With the TARP paybacks by Citi, Wells and BA, that crisis loomed but has now passed. The big banks did not fail. But they have failed to put their balance sheets to work in this economy. Banks borrow money at the discount window for approximately nothing, then charge credit card holders up to 31.99%. They can also buy Treasury Bills for 3.5% and pocket the difference. Does that sound like arbitrage or "dire straits"?