… for three reasons:
First, coordination. Even actors with purely virtuous motives would still need rules of property acquisition, transfer, and exchange for purposes of coordinating their activities. Property rules tell us who has the right to use which item and how we can interact with others through our property, allowing each agent to form expectations about the future and act in conjunction with others.
Second, information. A virtuous community still suffers from imperfect information about who should get what. In markets, prices communicate information about the nature and intensity of agents preferences without any single group distributing those goods on the basis of that knowledge. And on the production side, it will need the price system to determine how much and what it should produce to meet people’s desires.
Third, discovery. Markets have a discovery function whereby entrepreneurs identify unmet preferences or needs of others in the markets. Changing the motives of entrepreneurs would not affect the discovery aspect of markets. While entrepreneurial saints would perhaps not require pecuniary incentives, it would still remain the case that untapped or unmet preferences would remain unidentified without the process of market discovery.