This is a stupid idea. (It's even more stupid when they give away steel bottles -- manufactured with a lot of resources -- that students put on the shelf!) People are not forced to use bottled water. If you want to SAVE students from themselves and the environment from plastic bottles, then why not ban soft drinks? Sounds stupid? Yeah, that's my point.
Bottom Line: Bottled water is no more evil than peanut butter; plastic bottles are not worse than glass bottles. Pay attention to the real problem (litter, water quality, sustainable extractions), not just a business that is correlated with poor management of resources.