Q. A fellow, we'll call him Reuven, reserved and booked a seat six months ago, meaning he paid the cheapest fee (since he reserved early) on a flight in the Economy section. He arrived for the flight and approached the ticket counter with the following proposition. He had checked and saw that the plane had three open seats in Business Class and no open seats in Economy. He suggested that if someone comes to the clerk before the flight and needs to purchase a last-minute seat, the clerk should take his Economy seat and charge the newcomer what a last-minute seat in Economy costs and place Reuven in Business Class. The seat in Business Class was going to remain unoccupied anyway and the extra perks surely don't amount to much expense to the airline, whereas no the airline will obtain a bonus on an already acquired seat in Economy.
Is there anything unorthodox or unkosher about this whole arrangement?
A. Horav Shlomo Miller's Shlit'a opinion is that as long as the properly authorized ticketing officials that represent the airline agree to the deal you propose, there should not be a problem.
Rabbi A. Bartfeld as revised by Horav Shlomo Miller Shlit'a