These concerns seem pretty hypothetical because AI's going to be putting everyone out of a job before such things could be an issue anyway.
That said, even in a hypothetical primarily-human labor-market, market-dynamics would fix the problem anyway.
For example: say food becomes scarce because no one's farming. Then the remaining farmers would become rich (they could raise their prices tons) while everyone else would end losing their money to buy the food. Eventually folks would start going into farming until the imbalance is corrected. And, yes, this would mean that those who'd refuse to go into farming would end up draining their retirement funds away -- a retirement fund wouldn't be a permanent no-work ticket, at least in an economy where labor was in too short of supply.
At least, in an ideal free-market economy. In practice, we tend to simplify things and have regulations for practical reasons. Such deviations from an ideal free-market economy might mess up the correction-process.. at first. However, if such regulations did prove to be problematic and prevented the economy from working, then we could just change the laws/regulations to fix that problem -- the simple approach would be to simply repeal problematic regulations.
In short, the stuff you're worried about can't happen (because AI will take the jobs anyway) and wouldn't be a problem even if it could (because market-dynamics fixes such things).
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Separately, might be worth noting that the big future problem would likely be population-control. Once we have good AI/robotics providing exploding wealth, and then clinical-immortality, it'd be all too easy for people to just keep having endless babies. Doubly so when we have good enough 3-D printing to literally print people, and easy test-tube babies before that. That may be an issue society'll need to address.