I hate to disagree with you, however, the disciplinary issues within the USPS are monumental. This is an organization which on one day issues a letter of warning to a carrier for walking across a lawn where there is a dog, and a day later in the same office issues a letter of warning to a carrier out of the same office for NOT walking across a lawn and wasting time.

The carrier at your place of business operates under a different set off rules than a residential delivery. Carriers picking up at a business certainly have to pickup and make deliveries IN the place of business.

A carrier making a residential delivery is not allowed to pull into a driveway, make a left turn into a street unless authorized by a supervisor, leave their vehicle to make a delivery unless authorized by a supervisor, talk to a customer while making a delivery, and many other little rules which carriers routinely break. It's fine, nothing is said, until the carrier upsets management, than all the little rules they break (and have to break) while doing their duties come to the top.

If the carrier is on a walk route the rules are slightly different, but not substantially so.