Yeah, I've received packages in USPS boxes turned inside out and it really makes me think a lot less of the company that did it. The box looks like crap that way, the pull string is on the outside, and they are weak when they are ruined that way so the contents get crushed. It's pretty rich on the one hand to denigrate the Post Office for being short on money and on the other hand to take a box they gave you free with the expectation that you would pay them $10 or $20 to ship something in it, and turn around and pay a different shipper to take the package. To me it shows that you are an untrustworthy vendor and one I probably shouldn't do business with.
It's illegal too. Says it right on the box.
"Whoever steals, purloins, or embezzles any property used by the Postal
Service, or appropriates any such property to his own or any other than its
proper use, or conveys away any such property to the hindrance or detriment
of the public service, shall be fined under this title or imprisoned not
more than three years, or both; but if the value of such property does not
exceed $1,000, he shall be fined under this title or imprisoned not more
than one year, or both."--18 U.S.C. sect. 1707.