I was going to mention that you can get free ice/cold water inside the parks but someone beat me to it. You can also get free hot water at many locations. We do this as well at Disneyland. We don't object to the taste but if you do you can always bring those flavor tubs to add to the water. My DD12 does that quite often-to the bottled water or in the cups.
We are usually on the DDP when we go but I hate to use a SC for bottled water or sodas. We save them for something really good like an ice cream sundae!