Self-service checkouts have been in supermarkets for almost a decade, but the machines have produced a new breed of criminals who routinely shoplift, costing the stores a fortune.
"People who steal at self-service checkouts are very different to your typical everyday shoplifter," said Dr Emmeline Taylor from the Australian National University.
An anonymous survey of more than 7,000 Australians has seen one in three declare their hand in stealing from unmanned tills.
"And they may become distracted and they may think they've scanned something and they haven't, and then getting home and realising they've got these goods for free, then for some people it becomes quite addictive." said Dr Taylor.
"And they realise they've not been apprehended and it's actually very easy to get away with."
The big problem is with 'substitute scanning' for fruit and vegetables, for example purchasing cherries, but pricing for carrots.
"The cost of the wages to employ someone to man those checkouts should they not have self-checkouts there, must outweigh the cost that they are losing," said Carla Bridge from the Australian Retailers Association.
It is all adding to Australia's seven-billion dollar shoplifting bill.
At some stores Kmart is locking chocolate in theft-proof boxes, while Coles is tagging meat with security sensors.
7News reports there may not be an end to the free-for-all in sight, with both a shopper and retailer preference for self-serve at the checkouts, and more smaller stores are shifting to unstaffed registers as well.