As long as we are speculating... It's possible that the two individuals are engaging in illegal operations (drugs or money laundering)...
Hey Joe... I'll sell you this key of coke for 10k!
Ok... but I can't cary that much cash on the plane with me...
Hey Joe... I got these sharpening stones for 10 bucks at home depot and made them look old... How 'bout you give me $3,000 for them... We'll do that 3 times... That's 9K. You can send your old lady over to take care of the other grand...
It could happen!
I've actually thought about the laundering thing myself. If it looks like a fish, swims like a fish, smells like a fish, just might be a fish...