What are the strengths and weaknesses of the social contract?

Social contracts are imagined constructs of JS Mill, Thomas Hobbes and john Locke. All assumed societal relations are formed based on the fiduciary principle of exchange: I protect your rights, and your protect mine. The problem is, resources are allocated un-evenly. Invariably, the richer and powerful people would demand that their RIGHTS or Way of Life be protected first. US Constitution, for example, sought to protect the rights of the landed gentry before those of the slaves; whose rights had to be redeemed and protected literally 100 years later. Social contract theory, therefore, cannot correct the imbalances that exist between the different classes of people. It can only reinforce them; often leading to more embedded conflict, animosit and latent anger, all of which STILL make societies extremely unhappy----even if there is no open conflicts and warfare. But because social contract is self serving and self righteous, those that try to challenge it are often struck down, or, accused of being anti social. More psychic injury is therefore inflicted, as social contract is perennially maintained.