I’ve seen this a lot before. I live in a small midwestern city that is served by several airlines. I’m pricing air fares to Europe. From my city to Amsterdam via Minneapolis on Northwest is $226 CHEAPER than the Minneapolis – Amsterdam ticket for the same flight. From my city to Amsterdam on Northwest via Detroit is $150 – $200 cheaper, depending on the flight. This benefits me so I’m not complaining, but a negative relation between cost and price is insanity, even if it is easily explained by the logic of captive markets and near-monopolies in hub cities.