It encourages carpooling. It increases job satisfaction because if you have a bad job, you don't care. It eliminates vacations because people would rather come to work. It makes fellow employees look better. It makes the cafeteria food taste better.
Bosses are more likely to hand out raises when they are wasted.
Salary negotiations are a lot more profitable. Suddenly, burping during a meeting isn't so embarrassing. Employees work later since there's no longer a need to relax at the bar. It makes everyone more open with their ideas. Everyone agrees they work better after they've had a couple of drinks.