Context is important in this

1) HCT is, by many accounts, a rare occurence. It's also something that's not openly condoned or encouraged to any great degree, even here on FT.

2) More important, the airlines are the ones who have created what demand exists for people to engage in this practice. No one should lose sight of this. Sure, any Econ 101 student can blurt out "market forces" but people who are buying tickets (especially with their own money) are far more focused on actual value than nebulous market forces. And how does any airline try to construct an argument that an HND-IAD Y ticket has as much as four times the value as an HND-PIT Y ticket that just happens to go through IAD?

The airlines can choose to clean this up if it's really important to them. If it isn't then they shouldn't complain about it, either. My guess is they really don't complain about it, at least not nearly as much as some on FT think they should complain about it.