All companies and some self-employed people will be required to have credit card machines this year and Greek Deputy Finance Minister, Giorgos Mavraganis, has made no attempt to hide the motivation behind the move - it isn't just to tackle tax evasion, it's to collect data about citizens and where they're spending their money.
The problem with this is that the type of people who evade tax aren't the sort to take any notice of a law telling them they aren't allowed to pay more than €500 in cash for something.