Originally Posted by
Miles Ahead
I think you're attributing more thought to United than they put into it themselves. I don't think they thought any harder than "Not 50 states, and really, really far".
UA considers this an inter-continental flight. Same rationale as the northern South America routes (such as IAH/EWR-BOG) which now require a GPU. Obviously the decision is not based on the flight's service level, but rather the mere geographics.