The Super-Walmart in Leicester has this water refill system where you can buy a jug in a few different sizes (1-gallon through 5 gallon water cooler jug). It says it's RO water. You can buy the 5 gallon jug for $12.88, and then from what I understand, you pay 37 cents a gallon to fill/refill it.
Does anyone else's walmart have something like this? Have you tried it? Any problems with the water? I was thinking of going this route since I go through less than 10 gallons of water a week and don't really have much room to set up an RO/DI system and store the water it produces.