WA is the state code for Washington in the US, by the way. Is WA commonly thought of as "Western Australia" worldwide outside of the US? If not, maybe consider using less overloaded abbreviations in your titles.
My second reading was an assumption that it was a US state code (maybe I could have arrived at Washington if I thought for long enough about it) and that there'd be a comment here very much like yours but complaining about 'US defaultism'.
So no, it probably isn't that common outside of Australia, but this is so so common, and bear in mind it's usually a US thing. (Anything 'national' or talking about 'the nation' generally means 'the US' on HN, for example.)
The ramifications of hijacking the wifi used by frequent flyers/tech workers between Seattle <-> SJC/NYC/etc have a very different 'vibe' to it than the actual one in the article.