When it comes to saving money, HR departments educate themselves rather well in regards to the law.
This is where a little bit of knowledge is very dangerous. Companies read a small part of the laws and think it's very simple to reclassify hourly employees to salaried employees. It's not.
Also, this is why labor still organizes in the US, even if organization is down substantially over what it used to be.
And yes, if the workers had pursued legal action, I think they would have had a case, but these people were somewhere around lower middle class or poverty level and they were very afraid of losing their jobs. Knowing them, and others who are in similar situations, I completely understand and sympathize. When you're treated like crap, but given the illusion that you're respected and needed, you'll convince yourself that everything is "good enough." I myself did it for many years.
Look, I'm not hopelessly naïve (most of the time) and understand very well about standing up to what's right, but there's a way to do that without acting like this. Even if the person you're dealing with is a sociopath, even if they're terrible human beings, there are ways around them that don't rely to threats, real or implied.
Negotiation takes a lot of nuances, verbal and physical, but you can achieve a lot diplomatically without being intimidating physically.
I understand where you're coming from, but I disagree completely.
Edit: Also, I didn't downvote you because what you brought up was still interesting and allowed me to voice my opinion.
That said, some people can only think in terms of who can kick who's ass - for them might IS right. The stupid ones become muggers and extortionists, the smart ones get a system (legal, corporate, etc) to fight their battles for them.
I see no moral problem with presenting them with a simplified model of their worldview, it's their choice, I am just showing that I am willing to make it manifest.
Like I said, take with a grain of salt.