Re: post scarcity
I'm not sure you understand what a post-scarcity society is. Our current economy is based on the notion of scarcity of resources by necessity, because resources are scarce - at least partly because there is still the requirement for direct human intervention in the gathering and processing of resources.
More than anything, the single limit on economic activity is energy supply. The greater the supply of energy a society has, the more it will automate, because automation is more efficient than using humans to do equivalent work.
If machines are capable of doing "all the work" - running an entire economy from primary to secondary to even tertiary industries, then those machines would by their very nature be capable of gathering resources in ways that are either impossible or very difficult for humans.
The more energy a society has, and consequently the more automation it engages in, the more resources it can gather. If a society has reached the point where it can automate everything, then it follows that such a society will have enough energy and automation to gather effectively unlimited resources. It will have enough energy to make routine journeys beyond earth in order to gather those resources, as that, too, is only a question of the application of sufficient quantities of energy.
A society with effectively unlimited energy, complete automation and the ability to gather effectively unlimited resources will inevitably transition to an entirely different economic model as a result of these things. Post-scarcity means simply that: there is no effective scarcity of resources, and with absolute automation it becomes nigh on impossible to artificially enforce scarcity. Without scarcity, traditional economic models break down.
Notice that I did not say it would become some sort of socialist paradise, just that the economics of a society that can completely automate its industries will be radically different from those we currently understand or abide by.