Every year I usually spend 1 or 2 months in Korea. Perhaps the most boring country in the world as far as cars go (but excites me by the prospect I could import a Z from Japan so cheaply ). By Korean standards, a 5 year old car is too old, and a 2L 4 door sedan top of the range Samsung, Hyundai, and to a lesser extent Kia is a "luxury" vehicle (something we would call here a family car!). My view on the different Australian pricing was simply the demand for longevity in Australian vehicles, the longevity of value, and the higher social value we hold our cars at. Where as in another country, Korea for example, where cars don't have that same social and asset value, you can get by without them.
Also we need to consider the ridiculous value added situation that we have here. We export our raw materials and minerals for energy and production, which can be a network of travel through several continents in most situations, and then we finally get the product imported back here from the very materials that we sold!