What a remarkably narrow and historically inaccurate vision of slavery you have. Voluntary slavery is still slavery. It does not permit the withdrawal of consent, which is in fact a pivotal aspect of freedom. Meanwhile you continue to miss the point entirely: Free market ideology does not take into consideration coercion by private actors as a form of regulation. If it did, then free market ideology would acknowledge what it does not: That private actors must be restrained by a higher authority, the precise opposite of what it does argue. You are trying to impose a moral philosophy on free market ideology that has never been a consideration. The Invisible Hand alone is supposed to keep man moral, according to the myth of the free market.
It’s funny that you mention the Invisible Hand though. Since the person who coined the term also said,
“Men may live together in society with some tolerable degree of security, though there is no civil magistrate to protect them from the injustice of those passions. But avarice and ambition in the rich, in the poor the hatred of labour and the love of present ease and enjoyment, are the passions which prompt to invade property, passions much more steady in their operation, and much more universal in their influence. Wherever there is great property there is great inequality. For one very rich man there must be at least five hundred poor, and the affluence of the few supposes the indigence of the many. The affluence of the rich excites the indignation of the poor, who are often both driven by want, and prompted by envy, to invade his possessions. It is only under the shelter of the civil magistrate that the owner of that valuable property, which is acquired by the labour of many years, or perhaps of many successive generations, can sleep a single night in security.”