Moreover, who says that workers are paid anything like their marginal products? Luck and market power seem to me to be much more important than anything that could be called net social value of the work. As I often say, a skilled worker is an unskilled worker with a strong union:

Paul Campos: Talent Is Not Scarce: "Existing social hierarchies, and especially the compensation structures that undergird them, require the constant denial of the fact that almost everyone is easily replaceable at any time.  After all, if there are 500 people standing at the ready who could do just as good or better a job than Chairman Smith or President Jones or Senior Executive Vice President for West Coast Promotion Johnson or Distinguished Professor of the Newly Endowed Chair for the Worship of Capitalism Cowan, then why do these people get treated and most of all paid as if they were as unique as unicorns, as precious as Vermeer portraits, as irreplaceable as Billy Shakespeare or Willie Mays? Because if we didn’t treat them (us) in that way, that would mean the entire structure of our society is radically unjust, root and branch.  And that can’t be true, obviously...