There are necessary preconditions that need to exist for the ideal form of "voluntary exchange of goods and services for mutual benefit" to exist. The smoke screen that a lot of capitalists try to put up is to pretend that those preconditions exist when they don't. This is most obvious in employment negotations (whether between employers and employees or in determining government regulations) where, on one side, what the employer has at risk is typically something like a few points on their profit margin. By contrast, on the employee side, our society has been structured such that, aside from the wealthy elite who get to have "retired early" rather than "be unemployed", "having a job" is integral not just to being able to afford food and shelter, but also to social standing and self respect.