Such, basically, is the history of the world. Once we were all hunter-gatherers. Now that economy has almost completely disappeared, replaced by the complex system of land ownership and exploitation in support of vast urban populations. There were an estimated 6-10 million people in the world— the whole world — at the dawn of the agricultural revolution. Now there are around 8 billion, and the very real question is how many humans this increasingly stressed planet can support.
That pretty well sums it up.