The only problem is that each of these laws has robbed someone of their individual freedom. Dealing with abusive employers may be difficult, but when people refuse to work for them they change.
People won't refuse to work with them, because there's a lot of desperation, bad decision making, and generally messed up lives at the lower end of society. Employers--not all, but some, maybe many--will absolutely take advantage of that in the absence of regulation. Sweat shops, child labor, indentured servitude... that stuff belongs in the 19th century, not in modern America.