There is no reason to believe jobs with significant cash wages will always be around. If we eliminated prisons and police we don't need, the TSA, a significant part of our military, and other make-work and counterproductive jobs we would have higher unemployment rate, even after the economy rises from having the unproductive drag lifted. That is, our current employment picture is highly manipulated. The people in jobs that could readily be eliminated only have an illusion of worthwhile work.
I'm not convinced arguments about worthwhile are useful. If you're not involved in basic industry, then any job is the same, right? We don't NEED anything but food, housing and ... that's about it.
There are jobs that are objectively make-work positions, especially in the public sector, and the penumbra of "beltway bandits" where there is no individually expressed demand that directly or indirectly caused a requisition for an additional worker to, for example, touch your balls with a blue glove.
