And selfishness and greed are not sins in a free market. Instead, they serve as the mechanism under which everyone works together. A selfless man who strives for compromise will be abused by selfish actors in a pure free market setting.
All philosophies have their pros and cons. Learning to pick which philosophy is an art. Personally speaking, I keep Capitalist AND Communist arguments in my brain. I'm ready to use either philosophy to prove whatever point whenever I want.
For example, if you were a Communist, I'd deride the "free market" by talking about Bourgeois and the working classes. (But that wouldn't work on you, because you'd instantly think that I'd be creating a "class war").
All of these philosophies are theoretical anyway. The real purpose of them is to give us the ability to understand what other people are talking about. Furthermore, it has been proven that ALL pure systems are imperfect.
Free Markets have their market failures (Monopolies). Communists fail to allocate resources effectively.
The solution therefore, is to pick and choose the philosophy that works in the right situation. Be a more educated man, and open to different ways of thought.