I think we need codes of interaction. Agreement on what's the proper way to interact given the circumstance.
Afterall, we humans are social and interdependant individuals. Then agian, this applies as well to economy so if we rationally make the law system crumble for agreeing that all we need is norms, without the need for an entity to enforce them (lawls), and that we as individuals within a community can agree on them, then, this very same rationale applies to economic organization.
This is a basic interaction premise for me:
So long as all the parties involved in a relationship of any kind are aware entirely of the origins, implications and conditions of said relationship and are entirely consensual, that is they set and agree with the former, then that relationship is correct. Shall the relationship involve unaware, deceived and/or unconsenting parties, that is, ignorance, coercion and/or deception, that relationship shall not be accepted and members of a certain community aware of this situation, outside of this relationship, may intervent to assist ignorant, deceived and/or coerced parties into get rid of said limitations.
That's what morals and norms are for, aren't they? To establish the kind of interaction between the individuals of a certain community. If so, I think that premise pretty much covers in general any kind of relationship from economic to personal love realtionships.