forgive my ignorance, but is there something wrong with that? It’s something I’ve considered doing in the past.
Technically if you do it and get caught, the airlines have the right to deny you the return flight.
Yes, there is something terribly wrong with it: Peasants are punished if we violate so much as the spirit of the laws or rules. Elites are only punished for violating the letter of the laws or rules, if that. (Jon Corzine.) Clearly, if you book a ticket to Lake Tahoe, you’re supposed to go to Lake Tahoe, and anything else is fraud. When we do it.
I did it back in the 70s and was far from the first
i wanted to do this twenty years ago, cousin’s wedding in Columbia SC, aunt in Charlotte NC - had round trip ticket to Columbia, wanted to leave the plane in Charlotte on the way there. I couldn’t do it, said the agent, they would void my ticket for the return flight, they would have me arrested if I tried to board.
Today they’ll worry about you leaving an explosive device behind you - but if you wanted to do that, you’d just buy the more expensive ticket any way.
A couple years ago I was trying to book a non-stop flight to Ireland, leaving either Newark or Philadelphia. The least expensive flights were NWK-PHL-Dublin or PHL-NWK-Dublin. Obviously if they are selling NWK-PHL-Dublin there is a seat on PHL-Dublin but they won’t sell it to you for the low price - they want you to pay to escape flying an extra leg of the trip and wasting three more hours.
Nothing wrong with it if you're a passenger. Wife and kids drove to Atlanta and I was to fly to join them a few days later and drive back. One way flight to Atlanta was around $1,200, one way flight to Birmingham through Atlanta was like $600. Round trip to Birmingham was like $350. Purchased the round trip, didn't check any bags and got off in Atlanta. Nothing wrong with that.
I’ve done it. So what?
I’ve done this when flying from NY to Dublin Ireland. Found flights that changed in Dublin that were cheaper than a flight to Dublin.
It worked fine even on round trips as long as the return flight had a different departure airport.
Very simple: When you purchase a airline ticket, you agree to the airline's "contract of carriage," which includes a provision that specifically prohibits this practice. The UA contract, for example, reads as follows:
"J) Prohibited Practices:
1) Fares apply for travel only between the points for which they are published. Tickets may not be purchased and used at fare(s) from an initial departure point on the Ticket which is before the Passenger’s actual point of origin of travel, or to a more distant point(s) than the Passenger’s actual destination being traveled even when the purchase and use of such Tickets would produce a lower fare. This practice is known as “Hidden Cities Ticketing” or “Point Beyond Ticketing” and is prohibited by UA.
2) The purchase and use of round-trip Tickets for the purpose of one-way travel only, known as “Throwaway Ticketing” is prohibited by UA..."
Although the guy who runs this website isn't breaching his contract with the airlines (because no such contract exists unless he buys a ticket and engages in the prohibited conduct), he is arguably encouraging other people to breach their contract with the airlines and could be sued for intentional interference with contractual relations.
I’ve actually done this in the past though then you didn’t always know what your “hidden city” was, or at least if it was guaranteed.