The last time we went to the Keys, I stopped in Miami for gas. It was one of those stations that didn't have "pay at the pump" and you had to pre-pay. I took my credit card in and left it with the attendant so I could fill my tank. After I paid my bill, the clerk handed the card back to me and I noticed it was not MY card ... and the guy whose card I had, had already left (presumably with MY card)! What a frigging mess! He paid for HIS gas with MY card ... and MY gas was charged to HIS card. Luckily, they were both American Express and AmEx straightened it all out. They over-nighted a new card to me and it was at the hotel in Key West the following day.