However it was never her intention to discourage people from wearing masks and she "fully supports" all measures aimed at keeping the community safe from Covid-19.
She added all employees wear masks in line with the Ministry of Health guidelines and the shop encourages customers to "determine what's best for them".
"We trust they are acting within MoH requirements themselves."
A spokesperson for the Department of the Prime Minister and Cabinet (DMPC) told the Herald Delta's highly transmissible nature means face coverings are "one of the most important tools we can use to stamp out the current outbreak".
The spokesperson went on to say while having the sign up is not illegal, there are requirements in place for individuals to keep the community safe.
"At alert level 2 people must wear a face covering when visiting a retail business... it is the responsibility of each individual to make sure they are wearing a face covering in the places and situations required at each alert level, unless they are exempt. A person breaching the face covering requirements could be liable for a $300 infringement fee."
However the spokesperson recognised not everyone could wear a mask.
"There are genuine reasons why some people may be legally exempt from wearing a face covering, such as a disability or health condition. If someone has genuine reasons for not being required to wear a face covering, they're still entitled to access businesses and services in the same way everyone else is."
Among other criteria, a person can be exempt from wearing a mask if they have a physical or mental health illness, or condition or disability that makes wearing a face covering unsuitable.
Prudence Walker, the chief executive of the Disabled Persons Assembly, told the Herald people with disabilities are suffering because of anti-maskers.
She says people with genuine mask exemptions are being turned away from shops, as staff are focused on trying to deny access to anti-maskers.
"They've shown an exemption card [and been told], 'Ah yes, that's probably a fake'," she said.
Walker roughly estimated the population of people with past trauma who might apply for mask exemption could number in the thousands.