If you are using Garden Grocer or something like that just for water and other beverages/snacks, you might want to save yourself some money and follow this tip. It appeared in today's AllEars Weekly Newsletter:
I just returned from WDW and found a great place on the Disney bus route to get water without having to take a city bus to Goodings. The Hess Mart across from Downtown Disney West Side (Planet Hollywood) sells 24 17-oz. bottles of water for $4.99 (as well as other beverages). Take the DTD bus to the West Side stop and walk across the street to the Hess Mart. The DTD buses only stop at the West Side starting at 11 a.m. (which was something I didn't know). Thanks to the bellman at Saratoga Springs for the tip about the water.