A group of mystery fans were on a train, bound for their annual convention. It happened that there was also a group os salesmen on the train, going to their annual convention, to the same city. Each of the salesmen had their own ticket and they made fun at the mystery fans when they found out the mystery fans had only one ticket between them.
When the conductor started to come by and collect the tickets, all of the mystery fans went into the bathroom and locked the door. The conductor collected all the tickets from the salesmen, then knocked on the door to the bathroom. "Ticket, please." One ticket slid out from under the door. The conductor took the ticket and proceeded to the next car. The salesmen were amazed.
After both conventions, the salesmen were on the train returning home but only one mystery fan was (the rest had partied too hearty and stayed behind to recuperate). This time the salesmen had bought only one ticket between them and the mystery fan hadn't bothered to buy a ticket for himself. When the conductor started to collect the tickets, all the salesmen smirked as they rushed to the bathroom and closed the door.
The mystery fan went up to the bathroom, knocked on the door, and said, "Ticket, please."