I travel alone for leisure quite a bit and often meet up with friends who are flying in from another city. I leave checked bags on the baggage claim belt ALL THE TIME while I'm waiting in the lounge. I've done this in DCA, LGA, MCO, MIA, JFK, IAD, and others too.

The bags are sometimes still there, but most frequently they are at the baggage service office, and I just stop by and grab them. NOTE: I have very good travel insurance and high risk tolerance - I would not be overly angry (sure a little annoyed, but not too bad) if the bag went missing. So, it's at your own risk