While seeing both costs and benefits of markets, Adam Smith promotes free markets not only on efficiency but also on moral grounds. Commerce is intertwined with morals, it supports moral development and at the same time it is supported by it. For Smith, commercial societies generate wealth which supports life for an increasing number of people, institutions which support liberty, and social conditions which facilitate moral impartiality. Recent findings from experimental economics seem to support Smith’s ideas that markets and some aspects of morality are dependent on each other, and in particular that the causal effects of the relationship seem to go from markets to morality.
That is from an article by Maria Pia Paganelli, it is titled "Commercial Relations: From Adam Smith to Field Experiments."