Many corporate cheerleaders claim that corporations represent the "free market". Some do, sort of; but too many corporations do everything they can to get around a true free market.
A headline issue is "plnk slime" beef. Meat processors claim it is lean, finely textured beef and 100% beef. See "Beef Products Inc. Comeback: It's Not 'Pink Slime'; It's Safe, Nutritious, and 100% Beef". How can it be "100% beef" if it is treated with ammonia? Ammonia is not beef. In other words, the meat companies don't want consumers to have full information on their products. Full information to make a buy decision is one of the four requirements of a free market.
Many conservatives want "truth in taxation" from all levels of government, but they are often strongly opposed to "truth in lending", "truth in labeling", and "truth in advertising" for corporations. See above about full information.
Many food and chemical companies don't want products labelled GMO-free or rBGH-free. If genetically modified organisms or bovine growth hormone are truly safe products, why should companies fight labels that state products don't have these attributes? If they fight such labels, they must have something to hide, and thus they want to violate the free market principle of full information.
Many health insurance companies claim that the "Affordable Care Act" is against the free market and forces people to buy insurance. OK, the government is forcing people into the market. But the current insurance system keeps many people out of the health care market. And a parent is not free to leave the market when a child is sick. A requirement of a free market is being free to enter and leave the market.