Here is my response:
What rate of return for a capitalist is not considered greedy?
I would not begrudge someone any rate of return so long as they didn't screw their workers, the environment, people in other countries, or bribe politicians to rig the system to give them monopoly power to do so as oil companies and media companies have done.
In the case of media companies, we give them public airwaves essentially for free instead of charging market value, and allow them to combine to the point that they can choke out opinions they don't like.
We give an even bigger gift to oil companies: we use our diplomatic, intelligence, and military to give them control of Middle Eastern and other oil reserves, and overthrow any governments that threaten that control. In exchange, they don't try to increase production or cut us a break on the price, or even offer to repay the trillion dollar plus cost of the war even though they will reap tens of trillions in profit from it.
In some cases, like pharmaceuticals, we give the companies taxpayer money for research, and they thank us by charging us MORE than anyone else in the world, and fighting to keep those drugs whose development we funded from going generic.
Very often these same companies that we do so many favors for with our taxpayer dollars bend over backwards to get out of paying taxes themselves, so that they end up paying a lower percentage of their income in taxes than you and I.
Even if they got no direct support from the government, they used our roads, our police and fire departments, workers educated in our public schools, and other infrastructure to accumulate their wealth, so they should be grateful to only have to pay a percentage of their PROFITS instead of their INCOME like the rest of us do.
If somebody has a new product or idea that people want, I wish them all the profit in the world.
A better question to ask is what return should Americans be getting on our tax dollars? Should we get public schools with classes small enough for students to actually learn? Should we get meat inspectors who are more concerned about our safety than incurring the wrath of his boss who came from and plans to go back to the meat industry? Should we get a foreign policy designed to make us safer instead of more enemies for America and more profits for a handful of corporations?
If America was a business, and you were a stockholder or customer, what would you expect to get out of it?