It's odd to walk into a business that doesn't serve coffee. Most businesses serve it and set out styrofoam cups for employees to use. The average employee will go through over 450 coffee cups in a year. If a business were to buy every employee a mug, the mugs would pay for themselves in under a year in styrofoam cup savings. Most people prefer coffee in a mug anyways.
**image courtesy of Flickr Creative Commons