Interestingly, this flight (Sydney-Santiago, via Auckland) is one of a few that many flat-earthers insist does not exist, since it contradicts a theory they have. They'd plot the paths of long-distance flights on a polar azimuthal equidistant projection of earth[0], and note that some one-stop flights look like a straight line on this projection. But those which don't look like a straight line (i.e. that suggest they're wrong) are dismissed as nonexistant, and part of the greater globe earth conspiracy.
I flew many times between South America and NZ/Australia (and once from LA to Sydney, one of the longest flights you can get), including this exact flight, and find that's hilarious.
Yeah I've known someone (a family, actually) who did the same. In case you want a bit of light entertainment, the video where I learned about this is here - don't worry it's debunking flat earth, not in favour it: https://www.youtube.com/watch?v=2gFsOoKAHZg
Or maybe this is a high profile incident planned to keep the globe-head charade going! It is notable that the flight didn't actually go to Santiago in the end ...
[0] - https://en.wikipedia.org/wiki/Azimuthal_equidistant_projecti...