The answer, of course, is free markets. Yes, some businessmen are going to have more individual power than their workers. That's what collective bargaining is for.
So you are in favor of labour unions?
Why would I not be? Labor unions provide the individual worker with the bargaining power of the whole group. It's a great way to make sure the workers get fair treatment. As long as this doesn't get out of hand.
Trade unions are an example of it getting out of hand. When a union can restrict entry into a profession, or controls the entire market for that profession, then it has gained too much power, and the end result is the workers in that union start exploiting those who pay their salaries.
You can see this in action by looking at the medical profession and the automotive industry in the US. The UAW damn near strangled Detroit. The AMA is driving healthcare costs through the roof. (There are many other factors, but they're not helping .)