From the Daily Mail
The shopping centre prank is the latest in a string of NAB stunts. Another experiment involved the bank building a coffee stand on a busy Melbourne street, where the barista deliberately gave all customers $5 too much in change for their coffees.
Every single person immediately returned the money.
The barista then changed tactics and began insulting customers - asking one lactose-intolerant woman when she ‘decided she had that condition’, and telling a smartly dressed young man that he would no longer fit into his suit if he kept drinking moccas.
Despite the obnoxious comments 91 per cent STILL returned the extra change.