I used to work in the workers comp industry. Many employers require a pre-employment drug screen. If the candidate popped positive, they didn’t get the job. I suspect that drug screen may increase the likelihood of people getting a job, which can help many get off food stamps. Drugs also cause people to lose motivation, which increases the likelihood for prolonged food stamp usage. There is a chance that drug screen were implemented, in the long run it could save the program far more than the expense of the tests.