Yesterday I saw a man walking down the street holding an ADT sign. My first thought was that he stole it and I wondered what would make him want it. As they say, people will take anything that is not nailed down.
Then I thought better of it: perhaps he was an ADT customer going home to gently stick the sign on his own lawn.
Then I thought better of that: maybe he'd stole the sign from another house protected by ADT, so he could put the sign on his lawn to make it seem like he has a security system.
If that is the case, then I would not have been wrong in assuming he stole it, but wrong for assuming that he had no lawn of his own upon which to display the sign.