"There is no justification for Australians paying more than consumers in the United States for identical products," said Matt Levey, head of campaigns for the body.
"We have heard all sorts of excuses from the tech companies, like claims that Australian wages, rent and taxes are too high and that our warranties are onerous. Our research shows that none of the excuses stack up and the only conclusion is that the technology companies are greedy."
But Mr King said the price difference between Apple-branded hardware and software in the US and Australia was less than 10 per cent. This can be explained for some items by the inclusion of GST in local prices while US pricing does not automatically include state-based sales taxes.
Mr King is set to be joined by Australian executives from Microsoft and Adobe on Friday in a watershed moment for the committee, which has sought public hearings from the three companies since the inquiry began. The inquiry summonsed the companies last month to appear before the committee after several requests to do so.
Apple had earlier agreed to make a previously confidential submission to the inquiry public.
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