Fresh from reading the royal commissioner's "greed before people" mantra, Federal Treasurer Josh Frydenberg has latched onto another area of excessive bank profits: foreign transaction fees charged to debit and credit card holders.In order to provide a starting point, the Australian Competition and Consumer Commission has been asked to put an estimated A$2 billion in fees for foreign currency transactions under the microscope, Frydenberg said, citing the Productivity Commission's "Competition in the Australian Financial System" report released on 3 August.In announcing what will be, in effect, yet another government inquiry into the banking sector, it was the knowledge that "evidence from the Productivity Commission suggests these fees are higher than other countries, costing Australians hundreds of dollars more than in other countries per year," Frydenberg said.The Treasurer listed the main areas of concern as:•    converting money into a foreign currency;•    transferring money overseas;•    the use of debit and credit cards overseas;•    using debit or credit cards online to make purchases in a foreign currency; and•    transferring money to a foreign currency on a prepaid travel card.By way of example, an Australian bank customer who transferred $1,000 overseas would find the transaction cost, on average, around $80 in fees and exchange rate mark-ups, compared to around $60 for someone in the United States. "This means Australian consumers are paying 30 per cent more than those in the US for the same service," Frydenberg said.The PC report explained that, on average, credit card foreign transaction fees have increased from about 1 per cent in the early 2000s to almost 3 per cent in recent years - and questioned whether the fees charged are in excess of what it costs banks to process the transaction.Sally Tindall, research director at financial comparison site RateCity.com.au said the investigation would shine a much-needed spotlight on an area of banking that is riddled with fees. The average overseas ATM fee charged by Australian banks is $4.46 per transaction, but can climb as high as $5.50, she said. The ACCC's report is due to be delivered to Government early next year.