Can You Put Packages in USPS Blue Collection Boxes?

There is much confusion about the USPS' monopolies — that's right, there are two separate USPS monopolies The mailbox monopoly, mentioned above

Incoming Mail First class letters and parcel notifications are usually placed in TCU Boxes by noon · Outgoing Mail Mail deposited in the mail slot before 4:30

usps mail slot mail, like the ones still in use at the Madeira Post Office US Postal They don't even have a pull-down flap, just a tamper-proof slot

8 slot 500 series rack Brainstorming, I'm thinking the item might have been placed in another person's mailbox slot in one of the clusters, but some units are not