"Ban the Bottle" has linked to an article that describes the failure of banning bottled water, the site's own cause.
Although the article states reasons for banning bottled water that are rich for poking logical errors in, I'll stick with what happened at the University of Vermont.
Once the University of Vermont banned bottled water, sales of other beverages increased instead of students using the drinking fountain (intended effect). You can't take a drinking fountain into your classroom. Imagine that; students picking a different convenience.
Total calories from beverages rose by over 20 per cent on a per capita basis. The share of healthy beverages sold on campus dropped by more than half.
Read the article and shake your head. People never learn that banning is not a solution.