People being taken advantage of by unfair business practices are usually still making an active choice to participate in those unfair practices. People making below minimum wage would likely rather keep that below minimum wage job than be fired because the company refuses to pay them more. That is still not a valid argument against the minimum wage.

A business model that relies on unfair business practices is not a viable business model. We just need to make sure that the employees caught in this transition have a social safety net that protects them from the financial repercussions of implementing these higher standards for all employees.