A retailers' group wants the government to regulate the amount banks can charge for credit-card transactions.
Retailers in this country are charged a surcharge of between 2 and 3 percent of the purchase value, when a customer uses a credit or paywave card.
Retail New Zealand's general manager public affairs, Greg Harford, said that is three-times higher than what's charged in similar overseas markets.
He said the surcharge is added to the price of all goods, so those paying cash subsidise credit-card fees.
"So that means that the customer who's paying cash for their groceries is effectively subsidising the rewards programmes that are operated, air points credit cards for example."
Mr Harford said Retail New Zealand will talk to the government about possible regulatory solutions once it has conducted some more research on the issue.