"[E]xcessive corporate greed" is a subjective valuation ruled by the sin of envy...
If the corporation is too greedy not only does the market shun its output, but investors shy away from its stock. Whenever you see vacuous phrases like that you know you are talking to an economic illiterate who choses to blame their status in life on everyone but themselves.
Oh, what a pretty little theoretical economic world you live in. Everything works out perfectly in this pretty little theoretical world. Just leave it alone, remove all checks, and the GOD of the free and continuously growing market will take care of everything.