Of course the airlines will argue HND-IAD is worth more than HND-IAD-PIT. The consumer will argue HND-IAD is worth less than HND-IAD-PIT. Which side do you think the court will decide?
if this did go to court, the defendants argument of aaa-bbb is shorter therefore cheaper would be balanced against the plaintiffs submission of 10 years of revenue data showing the market value of aaa-ccc far exceeds aaa-bbb-ccc
no prizes for guessing that outcome.
You won’t litigated on this.
If you do this 'enough' You will lose the ability to travel on their planes and any miles accumulated.