In the case of the drug abuser, I'm not sure that incentive to spend appropriately applies. They're a drug addict after all - they really don't have a choice (other than rehab, but that also costs money).

Regardless, I'm much more concerned about the average recipient, who may need more gas than bread some weeks, or some other completely reasonable situation. As noted in a sibling, it's been proven that the poor aren't any worse at budgeting/spending than the not-poor.