Likely some sort of health insurance initiative. Lots of health insurance companies will give discounts to companies that can prove they have taken steps to improve their employees' health. So things like mandatory smoking cessation classes, drug tests, gym memberships, etc are all encouraged by insurance companies.

My former company actually did things backwards; They offered a $20 weekly stipend to anyone who committed to stop smoking via a monthly smoking cessation course. It was basically just a monthly 30 minute video you watched, then answered some questions about... You could do it on company time, so it was an easy $80 per month that you were leaving on the table if you refused. The backwards part is that they didn't offer the same stipend to people who never smoked in the first place. So all of the non-smokers suddenly signed on as smokers, signed up for the smoking cessation program, and immediately "quit" smoking so they could get that easy extra cash. I even used to keep a pack of menthols in my desk drawer, in case I was ever questioned about whether or not I really smoked. The first month they introduced the program, the company's insurance must have been screaming, because every single employee suddenly reported as smokers.