What you describe may very well be a valid definition of "Libertarianism," but Libertarianism's modern form (at least in the United States) seems to fundamentally rely on the belief that individuals are on equal footing with megacorporations and that therefore removing restrictions on said megacorporations will result in them acting in ways that are better for society rather than worse.

But, given things such as the historical existence of company stores/scrip and the things mentioned in Upton Sinclair's The Jungle, I find such beliefs to be overly optimistic: we already have historical proof that companies will fail to pay workers with real money and will sell unsafe food to the public unless forced to do otherwise by government intervention.

Companies have less "freedom" now than they did 100 years ago, and we are better off for it.