Why buy? Southwest's new Frontier

Maybe it's better to buy something because you want it instead of buying to collect a debt. That may be the lesson in Southwest's surprise bid for Frontier, the Denver carrier that ageed in June that it would be taken over by Republic Airways. Frontier owed Republic money and this way it could satisfy its creditor and keep flying. With Southwest ownership, Frontier flies for another year or two and likely gives way to Southwest's own Boeings after Frontier sells off its Airbus fleet.
What does Southwest get? It gets to bump United even further out of Denver, where UAL was always the big player. UAL now has about 35% of the Denver business, while Frontier has some 20% and Southwest has just 12%. Granted, that 12% is a lot more than Southwest's share at Denver just three years ago when it started up in the Mile High City.