Capitalism, driven by economic incentives does not address all the needs of a society.
Case in point is the "profit-before-care" syndrome being exhibited by the members of the Alabama Dental Association. Based on my understanding from the New York Times, Sarrell Dental Center is filling an important void -- one which private Alabama dentists are not. Sarrel operates a chain of dental clinics in Alabama seeing thousands of children without means to care for their oral health needs. But the Dental Association questions the quality of care while "lamenting that for-profit dentists face tough business demands".
Yes, a mission-driven sector really is necessary in a capitalist economy.