The only way we can
have anything resembling a free market for labour is if those seeking to sell their labour can be assured that failing to do so for a given period of time will not result in homelessness, starvation, and death.
In other words, until and unless we provide everyone with a basic income sufficient to support a modest living.
As it stands, and as you observed, pay for work is based primarily on some very old-fashioned notions of the value of the people who do the work—which is to say, anyone doing menial jobs is obviously a lesser being than those who tell them what to do. Then anyone telling them what to do is a better human being than their subordinates, and so on, until we reach the logical conclusion that CEOs are like unto gods (or at least kings), and must be treated as such.
This is not an indefinitely sustainable model, particularly in the face of increasing automation and increasing income/wealth inequality.
A basic income would result in people only doing the terrible jobs when there's actually sufficient incentive for them to do them, since they're no longer driven by desperation. Thus, assuming other external pressures haven't come into play, the wages for such jobs would rise until they actually compensated for the extra (sometimes literal) crap people have to deal with to do them.