Back in the 1980's, the USPS established some "contract post offices" in Albuquerque, NM, where I lived at the time. These contract post offices provided all the "in-house" services that the regular (government run) post offices did, but did not actually deliver or pick up mail. Workers in those contract p.o.'s were paid approximately 2/3 as much as regular postal workers and did not enjoy the terrific fringe benefits, and, if anything, were more efficient. I presume that they provided a considerable saving to USPS, but, having moved away from ABQ, I do not know whether they still exist.