I thought I'd add. I don't see employers being able to FORCE employees to do anything without the backing of government. In a voluntary society the employer and employee would decide whether they wanted to work together. They would not have to worry about government demands. They would not be FORCED to work for the employer.

There is the idea that they could be struggling and the mear struggle could be a form of coercion. Yet if you truly study such things, and particular bad monopolies I doubt you'll find any cases where that was not made possible and sustained due to government. I've been looking and haven't found any cases yet where that is not the case.