Can contracts be a valid means of formalizing agreement? Sure, but we have to introduce issues of consent. Consent cannot exist unless viable alternatives exist as well. Much like we shouldn’t evaluate individuals as if they lived in a social vacuum, or evaluate actions as if they took place in a causal vacuum, a contract can not, and should not, be judged in a vacuum, but rather must be contrasted with the institutions that sustain it. A contract may or may not be valid in itself, but if these institutions do not provide or allow any alternatives, then the contract cannot possibly be justified.