You're looking to small commerce, small contractors and overall "small" something.
If a guy's work worth 10, but his job is meant to be under a huge corporation to which you can barely find anything resembling concurrence, this corp. will pay him whatever less it cans.
Because your idea was actually voided by the Industrial Revolution, up to that time most business were small enough for concurrence to quickly kick in, after the Industrial Revolution you start to get enterprises and corporations that requires heavy investment to start.
Huge corporation or small business, it doesn't change the market wage. If said man's labor really is worth $10, then he'll find a job at $10. Might take some looking, but it'll be out there.
I know right now, I wouldn't take any job that pays less than $17/hr. That's what I value my labor at. Everyone has the same choice - they can choose not to work for $3/hr if they want. And if many people make such a choice, then an employer, even a corporation, will have to raise their wages to keep employees.
No one likes employee turnover. The companies that treat their employees the worst and that pay the least will have the highest turnover. They might have to replace their average employee once a month. All of that constant retraining and movement of employees can take a toll on management, co-workers, morale, and the general workability of the corporation. If a corporation did try to operate in such a manner (as some do), their customer service will be terrible, their sales will follow, and eventually, the company will cease to exist.
I'd rather let the free market take care of greedy corporations than try to regulate our way out of it and make things that much worse.
One example: Restaurants in my city are always PACKED. Uncomfortably so, to the point where you end up waiting quite a while to eat on any weekend evening. It would seem that there is much business to be had if you are looking to open a restaurant in the area. Unfortunately, there just aren't enough to meet demand, because if the restaurants couldn't overfill their facilities on a nightly basis, they wouldn't make enough money to pay the 20+ laborers the ridiculously high minimum wage we have here. Since they are forced to pay their workers a good deal above what their services *should* be worth, we have a smaller selection of crowded restaurants.
Is it worth it?