Here’s food for thought: Five years ago, the average annual income among food-bank clients was $11,200, according to Feeding America. Now, volunteers say they’ve served people who were making six-figure salaries.

As unemployment rose last year, the number of Americans using food banks jumped by 30 percent, the Chicago-based nonprofit reports. In a recent CNN interview, food-bank workers in the San Francisco Bay area said ten percent of the people they’ve served in the past month were new faces.

A growing number of these first-time clients are out-of-work secretaries, marketers, software developers, realtors and other professionals, they say. Many don’t qualify for food stamps, but are struggling with mortgage payments, credit card bills and other household expenses that are now cutting into cash for groceries.

And despite the initial embarrassment of relying on donated food, new recipients are finding a little help can go a long way in making ends meet.

At the same time, the extra traffic is leaving many shelves bare. Most items are donated by local grocery stores, church groups and the Agriculture Department, and a typical client will walk out with about $50 in free groceries.

A survey in December found that up to 70 percent of food banks and pantries were unable to meet the growing demand in their communities.

In January, Feeding America, which oversees a network of 205 food banks nationwide, lashed out at Congress for coming up short on emergency food assistance in the multibillion-dollar economic recovery plan.

"The lines at the food pantries and soup kitchens have grown longer and longer this past year, and unfortunately, we expect to see more and more hungry people coming to us for help as unemployment rates continue to climb," said Vicki Escarra, the group’s president and CEO.

Escarra said food banks were on the front lines of the economic crisis: "If we can afford more than $300 billion to bail out banks, surely we can afford $300 million to help our food banks."