Change fee, ha!
I had to change my travel plans coming back from Europe. Was supposed to head to the west coast, but now I needed to be in the midwest. It was cheaper for me to co-terminal in NYC and buy a new multi-city ticket stopping off in the midwest on my way back west. $200 change fee on international fares simply compounds the last minute fare class change. But note that I had no intention of using the last part of my original itin, as it was invalidated after skipping the flight. As a formal travel agent, I know the airlines don't specifically look for this, but if they find it, watch out.