When paper tickets were still frequently used, a practice existed by travellers to get rid of their tickets (which are person-specific), when they decided to alter the course of their trips. This practice consisted of selling the ticket to other travellers (often at discount prices), after which the seller accompanied the buyer at the time of departure to the airport. Here, the original owner checked in under his name and provided the airline with the buyer’s baggage. After this, the buyer boarded the airplane at the moment of departure. However, since most airlines check identification on boarding, this procedure is rarely functional.