Earlier quoted context omitted.
Or going into the baggage claim area with a bag containing an explosive device, then acting like they grabbed the wrong bag and putting it back on the carousel, and then leaving.
As an aside, this is something I've only seen in the US. At least in my country the domestic baggage claim area is not accessible unless from an arriving aircraft. I'm guessing that has more to do with theft though than security.
How do the arrivals exist the terminal
Are you not allowed to have a friend who is picking you up assist with baggage claim?