I think this premise is sufficient in any scenario where there are disparities in the distribution of a plentiful resource, as is the case in countries with privatized water.

However, when the resource is no longer plentiful, it is unwise to try the "let the market fix it" route (always a popular one on HN), because the resource in question can be consumed much faster than the systems you are describing can combat it (or can even be gotten off the ground.)