The post office has issues mainly due to the way they handle employees. However this shipping might not be that crazy. This is the model UPS uses. They ship everything to these big hubs because it is more efficient It sounds counter intuitive but if you have 10 offices It is cheaper to send everything to 1 location (10 trips) then back (10 Trips) then ship between the 10 sites (45 Trips). Plus the one large sorting location is usually more efficient cause that is all they do and they can bring in one set of expensive sorting machines rather then 10 or doing it manually at each site.