It doesn't really matter how "skilled" or "unskilled" a job is, what matters is how essential the job is and the availability of people willing to do the job. As we're seeing in many industries, people are striking to get higher wages, and companies are finding out just how much they need these "unskilled" laborers. A federal minimum wage is just accepting the reality that no matter how unskilled a job is, many are rather essential to the function of industry and society, and it's skipping the part where the workers have to strike to prove it to the corporations.