My weird experience for the day:
Standing in line to check in. The couple in front of me, booked to fly to London, are quite shocked and angry they can't not fly without a passport! They become quite angry, telling the agent that they don't NEED a passport, they are Americans! They seem to think getting louder and making veiled threats about someone losing their job over this will get them on the plane...
A higher up comes over and escorts them away to discuss the matter. As I pull up and say wow, hope that doesn't happen very often to you, the agent tells me that it happens much more often than you would think!