[bradleyjg]

> Simple: residential watering provides no economic purpose

You have an impoverished notion of economic purpose. Eating almonds make people happy, so almond growers grow almonds and sell them to people that want to them. Riding horses make people happy so alfalfa growers grow alfalfa to sell to people to feed to horses. So too, lawns make people happy so they spend a whole lot of money making sure they have neat, green lawns. That money gets translated into jobs and economic activity just like the money spent on buying almonds because they taste good.

There's no moral and immoral uses here, just satisfying preferences. The way to sort this out is through market mechanisms. It might be a different story if we were talking about pricing people out of drinking water, but that's not even close to what's going on here.