github is just one actor inside what you call voluntary market negociations.
I mean there no such thing as getting what you want. Both parties have to agree and if they do not, there no contract, if they agree there a contract. But that doesn't mean the company can force people to work for them or that on the contrary they are forced to provide a given level of compensation (outside of local regulation rules).
I work in India, where salaries are very low compared to USA or Europe.
I am just pointing out about the line pertaining to going to cheaper vacations, the truth at least for me is, some of the vacations might end up taking more than half of my yearly salary, which might not even end up as a month for a dev located in USA.
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