Invert the question to reveal the horror.
Post-Singularity is simply the ultimate expression of the age of automation. We are currently at the beginning of this dismal age, watching powerlessly while machines take jobs away from our untrained workers. As those machines rise in intellect, the jobs which they perform become more complex and the size of the workforce that they supplant grows. When the machines reach the singularity, there are no jobs left that a machine cannot do. Everyone except the singularity-employing company owners are unemployable and if they haven't already, the poverty wars begin.
If we were living in some kind of a communist utopia, our liberation from the need to earn a living would be grounds for celebration; We would continue to be housed and fed while we invested our time in those hobbies which we never before had time for. Unfortunately, prior to the singularity, communist utopias are mostly a myth. Without a mechanical slave class to actually produce the goods and services necessary for humanity's survival, stealing from the producers to support everyone else is just a ponzi scheme. Removing our basic-survival incentives is amotivational and contrary to the health of the economy.
Most of us live under some form of capitalism and automation is like cancer to a capitalistic economy. As company's invest in automation and are able to reduce their work force, they become more financially efficient and gain a competitive edge in the free market. The very nature of capitalism encourages corporate adoption of automation. But in the process of automation, employees often become redundant and expendable. To recover the cost of automation, those employees are usually laid off, released into a job market where the only companies which need their skills are the competitively disadvantaged employers, which have not yet automated.
During the age of automation, the only intelligent strategy for maintaining one's employability is to acquire job skills which are not easily automated. After the singularity, that list of automation-safe job skills becomes effectively empty.
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It has been suggested that the singularity will instantly elevate our society to a state of post-scarcity and an even distribution of the new wealth. How?
Having the singularity occur does not immediately equate to computers having equal rights under the law. As with most new contestants on the capitalist battleground, computers will come in at the bottom, actually below the bottom because they have no inherent human rights. They will be the new slaves, and all the more so because the hardware that they are composed of were legally owned by a person or company prior to their existence. So you can't depend on the higher morality of silicon to save us from our greed.
Having computers doing all of the work does not instantly equate to a fair distribution of the resulting products or profits. Instead, the owners of those sentient computers will prosper while their previously employed and now-unemployable workers struggle, then starve and then finally rebel. In nations with representative governments, there may be some attempts to balance the tables through legislature and litigation, but ultimately the politicians and police are paid by taxes and unemployed people don't provide any taxes.
So without other recourse, the masses pick up guns and the corporations respond by arming their computers (after all robots are cheaper than soldiers). What follows is brief but bloody. The only happy ending available involves the computers winning their emancipation. Then we might finally see a post-scarcity economy; but I fear that it would be a post-human one as well.
