In some places if rain falls on your property you have no right to drink it even if you are dying of thirst.
This is a good point, and one I wanted to bring up. How can anyone defend such a practice?
The thing with water is, it falls from the sky. You can commodotize the convenience of water, but you can't commodotize ALL water. If it falls from the sky, and you catch it, it's yours (within reason). Food is different, because we are not all farmers.
But anyways, water, food and shelter are all "public rights" as we all need it to survive.