How is social market structure different from capital market structure?

[Elmbeard]

One is set by the priority of public benefit, the other is set by the priority of return on investment.

There is no reason why one should be exclusive of the other:

A lot of sound investments may trade off maximising some profit by considerable social benefit, and is therefore worth doing and worth supporting, if necessary, with legislation and public subsidy.

Likewise, there is nothing stopping an enterprise that is primarily there to serve the public, also attracting private investment by making money, but then they must be strictly regulated, so they actually still provide value for money and do the job they are asked to do.

It can go wrong though:

Conscientious businesses could find themselves undercut by the unscrupulous, or bought out because their modest profits make them targets for takeover.

Public enterprises could be over-run by those whose only motive is to make money, corners are cut meaning that it becomes unfit for purpose, and the investors milk the public for what they can get, effectively holding the public to ransom. This has been well exposed on a massive scale by the antics of the banks over recent years, and the incapability of Governments to do anything about them.

Society breaks down when the powers-that-be decide to recruit those who set public policy from those who are primarily interested in arranging for themselves huge payouts, while those who do have the clarity of vision to administer public affairs well are consigned to their laptops on Yahoo! Answers, unpaid and ignored.