In some international cases, it creates tax/airport fee problems. Sometimes transit passengers pay less. Whether that's an airline or passenger problem probably

In some international cases, it creates tax/airport fee problems. Sometimes transit passengers pay less. Whether that's an airline or passenger problem probably depends. edit: I actually can't find any examples of "airport taxes" being levied on arriving passengers that are different than transit passengers. The differentiation only seems to be between departing & transit passengers) Meanwhile, other countries let you get a tax refund on unused flights and airlines probably hate that paperwork