A friend of mine within market anarchist circles, Xomniverse, made a concise and brilliant blog post related to this not long ago.
"A common argument I hear from socialists (both anarchist and statist) is that libertarians seek to impose the market onto people against their will. To me, this reveals a fundamental misunderstanding regarding what the market is.
The market is an abstraction and does not refer to something that is deliberately implemented. It describes the naturally occurring exchanges that occur between people in the absence of coercion. These exchanges, which are never done for the sake of creating a free market, occur because people mutually benefit from interaction and trade.
The market is similar to evolution in this regard. No animal ever acts for the sake of evolving. Rather, animals act for their own survival and reproduction naturally, and this results in an abstract process we call evolution. Both the market and evolution are examples of what is sometimes called spontaneous order, where an orderly system forms despite no intelligent being deliberately constructing the system.
Those of us (well, most of us) who argue for a free market are not arguing for a system to be implemented onto people by force. To the contrary, we see a naturally forming system that works better than any system that can be implemented by force, and we seek to remove coercion from human relationships so that this system can work automatically and at optimal efficiency.
The fact that socialists don’t see the market this way seems very similar to how some Christians don’t see evolution this way. They both see an orderly system and conclude that this system is implemented rather than naturally occurring. The socialist concludes from this that free market anarchists are out to impose a free market system on people, whether they want it or not.
But if the market just describes the natural interactions of people when coercion is not involved, what is a “free market system?” Any non-coercive social arrangement, even voluntary communes and syndicalist factories, would be a part of a “free market system.”
The point is, apart from a few abstract principles about non-aggression, the free market isn’t a system anymore than evolution is. The whole point of advocating a free market is that no particular way of life is imposed on anyone. When you look at it this way, it’s hard to imagine anything being legitimately called anarchism that isn’t a form of free market anarchism."