It’s a big number and it gets people’s attention when they hear it: 47 million Americans receive food stamps in what is now known as the Supplemental Nutrition Assistance Program (SNAP). The program has expanded significantly under President Obama, who boosted benefits and allowed states to waive some work rules under the American Recovery and Reinvestment Act. Still, the spiraling need for food assistance even as the unemployment rate has come down is tied to the weak economy and jobs that are so marginal that millions of working people earn so little they still qualify for SNAP.