Okay, so I’m a government that has collected $1 billion in taxes, do I choose the solution that provides water to 1 million people or 2 million people at the same cost.

Having a price tag isn’t just a feature of capitalism, it represents effort and labor. Even if we didn’t have money, we would be deciding if we should spend our villagers’ time building the water purification system that provides water to half the village or the one that provides to the whole village.