Many business buildings leave the lights on all night !
With new automation systems the lights can be turned off automatically when no one is in the room, and also turned on automatically when someone walks in the room. They cost next to nothing to install and can go much further than just lights, they can control room temperature and much more to save even more energy. New systems work wirelessly NO WIRES TO PASS! and are easy to use actually they're automatic no buttons to press nothing to do.
Here is a link to a company making automation systems... www.control4.com. My company installs these systems and everytime i drive around at night in the city and see the building almost completely lit up! I can't imagine how much energy is wasted