The market is not synonymous with capitalism. The market is merely a means to distribute commodities. It is independent of the capitalist method of production.
The market is just as capable of distributing commodities produced by a socialist method of production.
A free market capitalist system uses a capitalist production system, not a socialist one. And I disagree that socialist systems are "just as capable" as a free market capitalist system.
I don't know if you've realized but there is a word I keep using.
Free. As in freedom. In case you don't understand it, the word means you hold dominion over your choices. It means when I want breakfast in the morning, and I fancy some fruit and french toast, I can go to the free market and purchase these items and consume them, to my pleasure and satisfaction. Whereas, in a socialist system, I have a cup of rationed dry cereal provided by my master. And while, on paper, you may consider both to be equally capable of providing sustenance, I prefer the free market.