International travellers flying overseas expect the duty free products they buy from airport retailers to be cheaper than normal, however, this isn't necessarily the case in the UK.
Certain duty free retailers in the UK are scanning customers' boarding passes to avoid paying VAT (GST) tax and subsequently pocketing the difference, sparking uproar.
While the practise doesn't seem to have reached New Zealand yet, in the UK some customers have revolted and refused to show their boarding passes, which is not a legal requirement.
Auckland Airport spokesman Simon Lambourne said it wasn't happening in this country's duty free stores.
Mr Lambourne said the duty free and tax free stores at the airport scanned boarding passes, but for different reasons: to confirm the passenger was travelling overseas and for audit purposes.
"This is if a border agency or government wanted to look into it."
He said some information was also provided to the airport to "improve the passenger retail experience."
"For example, we take the flight number or country of residence and the amount a passenger spent in store.
"However, a passenger's name and other identifiable information is not provided to us," he said.
The Independant also revealed that some retailers refused to serve passengers who wouldn't scan their passes.
An Auckland GST specialist from accounting firm PWC, who did not wished to be named, said tax free stores at the airport, like all retailers, set prices according to the market, not a price that excluded the 15 per cent GST amount.
Therefore duty free stores are free to price their products according to what is appropriate.
The GST specialist said the market price and GST liability were a completely separate matters.
"It's the seller that pays the GST, not the customer.
"The market price is the price customers agree to pay."
JR duty free retailers at Auckland, Wellington and Christchurch airports sell products cheaper than normal retail stores, even when the 15 per cent GST is taken into account.
A 90ml Vikor & Rolf Bonbon perfume was priced at $237 at retailer Farmers.
On the JR duty free website, the same fragrance was available for $184 which was $17 cheaper after GST deduction.
Retailer Liquor King priced a 750ml bottle of Johnnie Walker Platinum at $159.99.
The same bottle is priced at $105 at the duty free stores, which was $31 cheaper after GST deduction.
A spokesperson at JR duty free could not be reached for comment.