The strongest argument for free enterprise is that it prevents anybody from having too much power. Whether that person is a government official, a trade union official, or a business executive. If forces them to put up or shut up. They either have to deliver the goods, produce something that people are willing to pay for, are willing to buy, or else they have to go into a different business.
People speak sometimes about the "bestial" cruelty of man, but that is terribly unjust and offensive to beasts, no animal could ever be so cruel as a man, so artfully, so artistically cruel.