In the early 90's I left a job that I had soured on and went to work as a truck driver (foolish choice). My route was the southern half of Seattle (we were located out by the airport). My habit was to load the truck in the morning, staging the freight on a "first out" basis. If my calculations were correct I would end up with an empty truck at the far end of my route and return to base for the day.
Then one day my bosses decided to invert the process with me starting my deliveries at the far north edge of my route and ending my day in my own neighborhood. It didn't take me long to figure out that the (unstated) reason for the change was that it made extra trips and (unpaid) overtime possible. There was invariably an order that came is during the day while I was out in the field that someone saw as a "rush" (or most likely a nice commission) and who cared if I had to go out again? I was paid piece-rate - I got paid for the poundage of the freight, not an hourly wage. If I had to make an extra trip it cost me dearly and I was barely making over minimum wage as it was!
I see a similar economic principle at play here. The Post Office isn't a profit center, it's a service. In order to contain costs they need to calculate their labor needs and utilize every cost saving trick they can think of. Unfortunately they can (and do) think of lots of ethically challenged tricks.
I've noticed recently that the mail trucks are at a dead run. This tells me that they are overloaded (or understaffed if you prefer), probably deliberately. They can't figure out how to work more efficiently so they've taken to adopting a Hobbesian Choice sort of approach ("I'm gonna give give you two choices - both bad. It's up to you to decide which you want to adopt").
I never ran a business other than a sole proprietorship so I don't pretend to know management principles but I do know how to live within my means.