market's aren't based on capitalism. capitalism is based on a particular sort of market. one where resources can accumulate, owned by a person, family, or corporation. i.e. capitalism is based on a market system where capital can accumulate. hence the name.
other market system prevent capital from accumulating, including, i assume, any truly anarchist market system. (an anarchist market system would have to prevent capital accumulating, because otherwise it wouldn't be anarchist. if a person was able to accumulate capital, they would then be able to have more power over others.)
what is a market? a market is simply a method of exchanging goods, resources and similar. they have existed long before capitalism, and i'm sure would even existed in an early communist society.
i have a particular aptitude at making bread and other baked goods. joan over there makes delicious stews, soups and similar. timmy is excellent at crafting eating utensils. it it could happen that we simply share all our food etc., or, we could exchange it instead. the result is virtually the same, we get a variety of food and means of eating it, and we remain free in each case.
so, why is the market based system not-free in this case?
ok, on a wider scale, looking at a community. a market based system (even if everyone gets the same amount of "money" to start with), allows people to decide what products are in greater demand. etc. (the invisible hand bullshit).
it isn't perfect, but it doesn't mean that the community is any less free.
so, what was my point? market's aren't nessecerily bad. though personally, i think that in the far future pure communism will reign supreme. to get there, we may use whatever tools avaliable. many people suggest anarchist-collectivism, which uses markets, as a form of 'transitional economy' towards communism.