Christina Victor, 19, was approached by staff as she left the shop on Sunday.
She says she was questioned repeatedly and when her mother approached staff, she was told her daughter "looked dodgy".
Glassons did not respond to requests for comment yesterday, but it is understood the matter is being investigated.
Mr Harford said although the incident was unfortunate, many retailers had policies for their staff to follow when dealing with a suspected shoplifter.
"Retail staff will be encouraged to monitor the situation and many retailers have got expert security staff in-store."
Up to $1.3 billion a year was lost across the economy - a huge amount both consumers and retailers had to pay for in the end, Mr Harford said.
Yesterday's Herald article about Miss Victor prompted others to share their own experiences of being wrongly accused of stealing.
Auckland graphic designer Megan Daggar, 43, said she was asked by a worker at a popular gardening store to show him the contents of her purse.
Ms Daggar, who has dark colouring, said the employee told her it was company policy to check bags. "The person he had just served before me did not have a handbag check."