By "without punishment" I mean "without losing a job offer you would have otherwise had."
See: how well you can lie. People study up for their tests even though you're not supposed to, lie their tails off on the physical questions, etc. I don't know when you knew someone going into the military, but nowadays you see kids lying about EVERYTHING. No kid wants to lose out on a paid college education and a job because they had an asthma attack when they were 14: so they lie their teeth off, and not just about drug use.