It's a lot more complicated than simple wage comparisons.
A friend just bought a freestanding, 3 bdr house in an upper-middle suburb of Houston for 87k (the mortgage slavery in oz is worthy of a legion of social studies). Cars are much cheaper. Petrol (all energy), food, clothes, are all undeniably cheaper.
However, typically in the first few years of commencing any job, you get 2 weeks annual leave. How do you value that? Healthcare is off the charts. The average salary is lower (and dramatically lower for certain jobs- such as pilot!).
It's not such a straightforward comparison.