[riskable]

It seems to me that this is a straightforward monopsony problem: The workers are already at what could be the best job they can get and yet the conditions are still terrible.

They can get a job somewhere else but it won't be as good. Better to protest/strike at their current job than go somewhere else. Especially when you consider that there's no reason why their current employer can't pay more and improve conditions other than greed.

If there was more realistic competition in the area for workers then the pay and conditions would never have gotten to this point.