The practice of letting individual store or area managers interpret corporate return policy is ludicrous at best(Sears insn't alone in this). Do they also let these same individuals interpret state or federal law regarding employment, sexual harassment in the work place, or pension benefit eligibility- of course not. This is simply a matter of being able to publicly proclaim a policy, then allow its subversion by underlings who may indeed be castigated for "excessive" utilization by customers of such a policy.
Your only recourse is to take it to the top but don't expect permanent changes, as they may satisfy you only to silence you; obviously the status quo will remain until 60 Minutes or some such investigative organization pulls this one out during a ratings sweeps month.