Laurie Blyth, owner of the Frontrunner store, has told customers not to use the in-store sizing service, and then buy cheaper online.

Blyth has put up a sign outside the store saying staff will ask customers if they intend on shopping online before they fit them.

Consumer NZ chief executive Jon Duffy says this will be difficult to enforce as customers could just fib, but there's nothing wrong with this move.

"They also absolutely have the right to ask the question, and if someone says - yeah, I'm just using the sizing service you're paying for to size up a shoe so they can buy it online, it's perfectly within the shopkeeper's rights to say they're not going to offer that service." 

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