Charities are naturally reluctant to turn down donations for fear of alienating supporters or demoralizing well-wishers, but the reality is that dealing with sporadic surges of cans is a logistical headache. A nationwide network of food banks called Feeding America gingerly notes on its website that “a hastily organized local food drive can actually put more strain on your local food bank than you imagine.” Food dropped off by well-meaning citizens needs to be carefully inspected and sorted. A personal check, by contrast, can be used to order what’s needed without placing extra burdens on the staff.

“For a long time we just basically kept politely quiet about the fact that food drives weren’t as helpful as people assumed,” explains Greg Bloom, a development assistant at Bread for the City in Washington, D.C., “but that changed when we became more diligent about stocking our pantry with healthy foods.”