Actually, this made perfect sense to me considering stores and casinos have been known to pump odors (and sometimes pheromones) through their vents in order to get people to stay longer and act in desired ways. The idea of expanding that to venting a gas manipulates employees was even a major plotline for Firefly. (I also remember when news was announced about the invention of anti-narcolepsy medication that let you stay awake for 2 days without feeling the effects...we were all joking that EA was going to stir into company coffee pots.)