I never spoke on the ethics of it.
Personally, I think I had it happen with UA on a SIN run, but the calculated difference was only in the tens of miles....and if I really did care about it, I could have booked a different routing and not traveled with my friend.

While I may think it isn't right--I just think it is useless to complain about it here, and stupid to complain about it most elsewhere (staring down consumerist.com).
As I said before, it is a legacy of times past. Unless it is changed at a governmental level, I don't see any airline listening about it or having any sympathy. It is legal, it is how routes are filed, and it has limited/minimal positive aspects for both the flier (save a few bucks in taxes) and airline (give out a few less miles).