[mrsmith]

JUNK MAIL!
I believe the law requires them to deliver it at below-market prices.
So they make it up elsewhere.

Everyone should boycott the USPS until it’s rates change so that junk mail is no longer subsidized by the other mailings.

[muawiyah]

The law requires them to handle the various classes of mail at the actual cost ~ plus an institutional contribution.

Read the law on the matter some time.