The value of labor is determined by the intersection of what the employer is will to pay and what the worker is willing to accept. All other values, including those invented by bureaucrats, are fictional. I don't know what this value is for workers other than by myself, and neither does the government.
When minimum wage is set above the actual value of the labor, unemployment increases, as employers reduce their costs. They can do this by moving, substituting capital for labor, or by hiring a smaller number of skilled workers to replace unskilled ones. Or, simply, by shutting down.
Laws requiring mentally disabled or other low-skilled people to earn higher wages than they are actually worth will render them unemployable. A low wage that is on par with skills is better than no wage.
Workers being housed in poor conditions or otherwise abused are appalling, and minimum wage laws are completely unnecessary to address the issue. Laws about employment health, safety, and cheating employees are a legitimate function of state governments. Wage and price controls are not.
I disagree, we are not a pure capitalist economy, nor will ever be one, ever! Regulation creep has happened since the dawn of our constitutional republic, multiple some ones screwed multiple some ones over and laws were enacted to prevent this from happening. Regulation creep isn't going to be undone in our lives either.
A mentally handicapped person isn't going to be doing high end machining that pays really well, but they can do dishes just as well as someone who isn't mentally handicapped, so why shouldn't they be paid the same minimum wage as the one who isn't handicapped.
Minimum wage type jobs aren't just for the high school kids trying to buy his first car or for retired folks. There are single parents who can't work a regular schedule, people that have mental disabilities, physical disabilities, care givers to elderly or handicapped relatives, etc. Would you rather there be no minimum wage laws and just put all those people on welfare?
Right now, currently where I live, there is no need for a minimum wage law because there are more jobs than people to fill the positions, like I said in an earlier post, it's pretty easy to get $15/hr to work at a retail or food establishments. Some of the corporate owned ones are offering hiring bonuses of $500-$1000 if you make it past 90 days with a good attendance record.
In regard to the working conditions in the article I referenced, the handicapped people were employed through a labor agency who provided the handicapped workers to the turkey processing facility. They took the money from the turkey plant and "divided" it up amongst the handicapped workers in terms of reduced pay, and subpar room/board. This was in the local news for months here.
In my younger years, when I worked fast food or retail, there was always a mentally handicapped person or two that worked there. Usually it was a dishwasher, bus boy, custodial, stocker type positions, but they typically worked properly and harder at their job than the other workers doing the same thing.