It had to happen: slapping the greedy hand reaching out to sup at the trough of plenty. This CNN report details a new way colleges around the country are cutting down on food and water waste, while at the same time helping keep students hungry.

It's a simple idea really: Stop stocking college food halls with the common food tray. Colleges around the country have excised the trays from their larders and are seeing some pretty green results.

Two nationwide surveys conducted by Aramark, the country's largest university and college food servicer, found a 25-30% reduction in food waste per person when trays were not available. Makes sense -- especially when your eyes are bigger than your stomach during the lunch hour. Basically this means making students eat only what they can carry. You can imagine the cost savings for university and college food service providers.

And you can imagine the grumblings of hungry college students. Maybe they haven't learned about "going back for seconds" yet.No trays mean fewer dishes to wash as well. Georgia Tech has reportedly saved 3,000 gallons of water a day by not using trays, according to the CNN article. The University of Florida estimates that it will save some 470,000 gallons of water annually by eliminating the tray.

Colleges and universities looking to go greener might do well to look at this simple solution. Less food and water waste by simply taking away the tray? Why hasn't anyone thought of this before?