Originally Posted by
WineCountryUA
... is where AAA-BBB-CCC is cheaper than BBB-CCC. And then that leads to
Hidden City Ticketing which makes the airlines unhappy.
You've got the last part of that backwards. Hidden city ticketing only plays a part when AAA-BBB-CCC is cheaper than AAA-BBB.
A cheaper BBB-CCC doesn't help, as your ticket is going to be canceled the moment you fail to board AAA.