We have a similar situation here. Sunnyvale and Santa Clara are adjoining cities, but served by different main post offices (San Francisco and San Jose, respectively, if memory serves -- rather a gamble these days). Mail from one to the other can take three to five days for delivery. Even Sunnyvale to Sunnyvale often takes two days, because all the mail is trucked up to San Francisco. There used to be a "Sunnyvale only" box at the main Sunnyvale post office, but they removed it a couple of years ago. They said something about "efficiency".
As my wife says, the handbasket is accelerating.
Mark[TELECOM Digest Editor's Note: Does anyone remember when we used to have _two_ mail deliveries each day as a routine thing, and when postage cost only a few pennies at that? PAT]