Yes, I agree.
America's Constitution does not prescribe Capitalism either -- it is just that, when left reasonably free from government's interference, people will form corporations, for those are the best wealth-generators known today.
In other words, America's Capitalism is a product of our Human Rights... In contrast, China and Russia dabble with Capitalism, because we've demonstrated it to be the most efficient way of organizing economy...
We have pizzerias not to "feed the workers" (for which they or may not be a different way), but simply because there is no way for the government to preclude one from baking and selling pizzas here (although various "licensing requirements" are steps against that freedom).
no they are a bunch os anarchist nuts
Getting a consensus among libertarians is like herding cats.
Freedom and market capitalism, not so-called crony capitalism where phony "capitalists" go to service the private parts of politicians in exchange for government preferences.
Libertarians want the state to enforce private property rights and only private property rights. That is the essence of capitalism.
I'm not sure about your first two sentences but yes libertarianism doesn't specifically specify an economic system and is more concerned with an individual's liberty. But I'd say 99% of libertarians believe in the free market.