mahasamatman means that someone might be flying TPE-LAX-PHL; that person would have to connect to a domestic flight in LAX. UA might want to save some of those precious 8 F seats for someone who paid . . . large dollars . . . to fly between PHL and TPE in a premium cabin instead of "giving those seats away" to someone paying the $700 QUAUP fare. (Also, note the ~$450 7-day NR QUAUP in this market).