Coffee may be addictive, but it improves long term health and short term quality of life. It's like being addicted to going to the gym for a moderate workout 3-4 times a week. (Tea is similar, though the health-promoting compounds are different.)
About nicotine in the office: ugh. This is a lawsuit waiting to happen. I don't like it when my coworkers bring junk food to the office to share, for the same reason. It's a more moderate version of having dangerous drugs in the office. But now a company is bringing actual dangerous drugs. Nobody's going to overdose, but people will end up addicted and it will contribute to heart disease. Hopefully they will stop before they shorten someone's life. (The common legal test for causation is "but for", as in "But for the company giving out nicotine, would the plaintiff have become addicted?" Unfortunately it's harder to answer if a decades later heart attack would have occurred if not for free nicotine. There is a true mechanistic answer, but we can't presently prove it.)