I imagine its like most things, they use to think that taxing things from overseas can make buyers by Australian made and save jobs here.
Well it may stop people importing higher end cars, let's say you buy a $100,000 second hand Shelby, on top of import costs you add 10% so that's over 10k in taxes.
That may just be enough to break somebody's bank and decide to buy something cheaper locally.
It works similarly at the smaller end of the scale, it won't scare off those with money to burn but if you're scratching to get just enough money to buy the damned things, that extra kick in the nuts may just put you off.
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