Are corporations "good" entities or "bad" entities?

I am reading repeatedly, only on Fluther, about the terrible power and influence of corporations. At least that is the way it is coming across to me. What am I missing? I personally have never been harmed by a corporation (unless you count Cracker Barrel Restaurants corporate policy of “managed mediocrity”). I am well aware of the culture of any given corporation, but that relates mostly to employees. What’s the beef?