There is a fair amount of literature in the field of economics on effective,self regulating and contracting groups that don't require a third party human authority to enforce contracts. In fact, the 2009 Nobel Laureate for Econ was actually in said field.

Many of the solutions aren't perfect, but neither are the human authority alternatives. The question to ask is, on the margin, is having a human authority more efficient than the self-regulating alternatives?