The biggest problem I see with Shermer's whole "Capitalism promotes morality" idea, is that capitalism requires a morality to make it socially acceptable. This morality may be unnecessary or different in another kind of economic system.

Yes, capitalism may lead to a set of moral rules that we place on it during its growth, but they would be rules we otherwise would not need in a non-capitalist system.

I am not totally anti-capitalist or anything, but it's somewhat similar to religion. Just like many Christian morals have developed or evolved based on the development on our moral philosophies rather than being rooted in scriptures or churches, so have we developed moral guidelines, tweaks, and regulations to our capitalist system which come from us, rather than stemming from capitalism.

Saying that capitalism promotes morality is like saying guns or the internet or medicine promotes morality because we create rules and regulations for them.