It's a crime to not go out of way to do someone else's job for them?

I see nothing about that here: https://www.law.cornell.edu/uscode/text/18/1701

"Whoever knowingly and willfully obstructs or retards the passage of the mail, or any carrier or conveyance carrying the mail, shall be fined under this title or imprisoned not more than six months, or both."

Reading/trashing mail in my box isn't obstructing or retarding anything in passage or conveyance.