>This imposes a limit on private ownership because if private ownership exists for the sake of the common good, then it cannot be the case that the private ownership of something is harmful to the common good. If I bought up all the arable land in the world and in this way prevented the possibility of farming and food production, I would indeed be harming the common good. Water is similar.

But nobody is actually buying up land so nobody can grow food, nor is nestle buying up water so nobody can drink it. In fact they're doing the opposite. They're taking water from the ground and selling it so people can access it. I don't see how this is any different than a farmer growing food from the ground and selling it to people.