Walter Block and Tom DiLorenzo have looked at Constitutional Economics, and determined that politics are not just another market. There is only a curious analogy to the public choice approach. Social contract theory has been used as an excuse for all types of state intervention.
Just because we do not all commit mass suicide does not demonstrate that we have all consented to some social contract. The origin of commonwealth was force and violence. The state is economic exploitation of the majority tax-payers by one ruling tax-eating group within government. Government is force. Submission to force is hardly voluntary.
Lecture 10 of 10 from the Steven Berger Seminar: Thomas DiLorenzo on Liberty and American Civilization.