Originally Posted by Biggie Fries

It's the airline equivalent of a "convenience fee." Just as there is nothing convenient about a convenience fee, and something costly about it, so too with the "one flight number" for two disjoint flights that don't even feature the same airplane. It's a convenience for the airline -- marketing a "direct flight" to folks who are not paying attention; and scamming us FTs out of some miles.

Or maybe I'm missing something, too.