"Pay is determined chiefly by supply and demand in the labor market. Jobs that are more fun pay less because the supply of workers is higher. Fairness is literally not part of this equation."
I think the implication is that society and technology have advanced to the point where, ostensibly, work that can't be automated away should be work that would demand a living wage. If it's tenable for my job to still exist, it's tenable for it to pay me enough to live. If it doesn't... well, that would be less a function of higher level characterizations of the economy or any individual job and more a function of the basic availability of food and housing, anyway. If there isn't enough food and housing, people start dying, but since there does seem to be enough of those, what is happening?
I work retail full-time. It's definitely not "fun," and I definitely can't afford to carry my own weight; I have to rely on family to make ends meet, and I know people who rely on welfare. In regards to the time and opportunity cost of working that job in relation to compensation, it is unfair (imbalanced), but the situation emerges from a context defined by labor's complete lack of leverage, juxtaposed with the, perhaps, overcompensation of the people who support us, encompassed by our mutual desire for society to not collapse.
I think it's funny that you mention $50/hr for delivering papers as if we should be aghast at the mere thought. If it's a job that needs to be done to secure the solvency of the overall business, and that's what it costs to live in the area where whoever holds that job must live, then... that's the going rate. If someone can live on less, they get the job and are paid less. If the business can't afford to pay a full time wage for a full-time paperboy (or a commensurate wage for a part-time one), maybe we don't need or can't afford paperboys. But as a society, at some point it would be prudent to look around and see whether the way people are living is sustainable, or if, say, the inopportune removal of a welfare or familial wealth Jenga brick would cause the entire tower to collapse into, like, tent cities or whatever.