"It was kind of a shock to be told I couldn't use the language I use all the time," she said.
Dame Susan Devoy said yesterday Miss Clarke should contact the Human Rights Commission and work with mediators to resolve the issue "amicably and positively".
She likened the case to that of iwi leader Naida Glavis, who was nearly fired for saying "kia ora" while working as a Post Office telephone operator in 1984.
"I had thought the days of people being censured for speaking Maori were over but perhaps I was wrong."
KiwiYo staff were expected to follow a presentation policy, involving a six-step welcome for customers.
Miss Clarke's employer, Margaret Lang, said the issue had been "blown out of proportion by making it a race and language issue, when simply, it is not".
Ms Lang had earlier said it was acceptable to rule out the use of "kia ora" stating "this is an English-speaking country".
However, after the protest, she told the Advocate that "if she had said 'kia ora, welcome to KiwiYo, have you been here before?' I would have had no issue," she said.
She said she had three Maori staff members and "was not a racist".
Yesterday's protest was organised by Hone Harawira and the Mana Party, and protesting teens came from as faraway as Auckland.
At lunchtime, chants began to lift while hordes of pupils from Whangarei Intermediate School marched on to Cameron St and began a passionate haka.
The school's team leader, Katarina Harrison, said they wanted to support Miss Clarke and the Clarkes.
The pupils from Years 7 to 8 were part of the bilingual Te Whanau O Waimirangi team.
Student Pakiohewa Roma, 12, told the Advocate he thought the people of Aotearoa should not be questioning the Maori language.
"What has happened here is disappointing," he said.
Meanwhile, Maori Language Commission chairman Erima Henare said Miss Clarke was owed an apology.
Mr Henare said that with te reo Maori widely taught in schools all New Zealanders under 30 were now embracing the language.
Ere Pene, 20, from Auckland, travelled to support Miss Clarke yesterday. "This is our native tongue. We should speak it freely."
Her brother, Kereama, 23, said: "It's something so minor to others, but we need to speak from our heart and keep our language alive for future generations."
Nasya Pene, 21, said companies need to check their policies around the use of te reo Maori.
Natalia Parore, 21, from Whangarei said she believed any efforts to stifle passion for the language should be seen as racism. Tayla Puru, 15, from Whangarei, agreed.