Why avoid all year round? Especially if flying round-trip?
Why get in shaalos about Shabbos?
Some people might be shocked to find out that there are Yidden out there, who feel more inconvenienced by putting themselves into halachic shaalos than having an ostensibly longer journey, or having to miss out on certain things.
The bottom line is that there are a few Chassidim in Australia who avoided crossing the international dateline (IINM instructed to do so by the Rebbe). Yeshiva shluchim to Australia also always flew with a stop in EY (and IINM also stops in the UK or Europe) on the way.