You know, I just realized I could buy a thousand dollar bill on Ebay. Son came by and looked over my shoulder:
"Hey Dad, what'cha looking at buying"
"Thousand dollar bill""How much does it cost?"
"About $3,000"."I think you're getting shafted" says my son...
Yeah, he's a little bitcoiner too....

Ah, the pains of fungibility. If each dollar carried the buying value it had when it was "minted", it could be a legitimate trade.