As a practical matter, that doesn't work when the power imbalance is so great that one side doesn't have a realistic way to negotiate the contract. I.e. if the

As a practical matter, that doesn't work when the power imbalance is so great that one side doesn't have a realistic way to negotiate the contract. I.e. if the best job that someone can negotiate is one where they are being exploited or abused, then that doesn't make the exploitation/abuse any more just.