DerbyDad03 wrote:
"...the postal service may stop delivering mail if your box
doesn't have a red flag. The flag directs the person-person (used to
be mailman) to pick up outgoing mail. "

I'm not arguing as much as I'm questioning the logic here.

Why would the person-person stop *delivering* mail just because he
didn't know if the customer had any mail to be picked-up? On days when
there is nothing to be picked up (s)he's still obligated to deliver
what's in the bag.

If the box doesn't have a flag, the box doesn't conform to government
regulations. If the box is non-conforming, the postal service may decline to
service it.

In reality, it's just one more reason the postal service may get on your
case. ("It's too high off the ground, it doesn't have a flag, it is not
lockable, it's painted the wrong color, and made of unapproved material, and
we don't like the dog much either!")