> So it's downright weird to keep hearing Australian accents no matter where you go.

No stranger than hearing English or French accents IMO. Or Canadian. etc.

> BTW, have you travelled anywhere, or is this "most have never travelled anywhere" just something you've heard?

I've been to just over 60 countries so far, and spent about 7 years basically backpacking straight, and plenty at hostels.

That's what colored my cynicism of "Australians travel so prolifically" - most of the time they just had short stops in a city and were there to get drunk. Maybe doing some guided tours as you point out, but rarely going off-road or actually traveling, meeting locals, learning about the culture, etc. You could say many Australians are tourists few are actually 'travelers', if that makes sense.