Originally Posted by number_6
The reason that airlines do this is to move higher on the flight list when routings are displayed. This in turn increases sales for that airline. It is a dispicable practice, but legal and some airlines do it a lot more than others. They pick routes on which they are not competitive and create these "virtual" routes just for marketing purposes. It is particularly bad when the aircraft types are not compatible -- so you cannot have the same seat assignment for both legs of the same flight number!
Well, spank my monkey - I thought they did this either because they are incompetent idiots (few would disagree with this), or because they get a sadistic joy out of messing with us. I especially like the "through" flights AA has at DFW, where you don't have enough time to deboard, change terminals, and reboard before the next boarding call.