many years ago I bought a book that had CAD $3.99 and AUS $7.99 pricing on the back. The Australian dollar was worth about CAD $150 I think. This book was almost 3 times as expensive in Australia. (I live in Canada). I was rater shocked and feeling sorry for the Australian readers.
If I lived in Australia I would be circumventing I am sure. The Australian government is all for it I have read.
Myself I wouldn't bother for fiction books (too many choices of books to read already), and probably not for price either on non-fiction unless we were talking big numbers.
But in the past (pre internet) I have gone to great lengths to get obscure or out of print nonfiction books. Dozens of hours on buses going to different libraries, and bookstores. Felt like I struck gold when I did manage to find one though
Helen