Among those is veteran Glen Innes state house tenant Niki Rauti, who faces a second eviction hearing this month.
"I'm here to look at this trophy and it's disgusting," she said.
"It feels terrible. They are making fun of us."
Sue Henry of the Tamaki Housing Group, which organised the group of about 10 protesters, said the $1.5m sculpture was "a trophy to Barfoot & Thompson" - the real estate firm that paid $1m towards it to mark its 75th birthday.
Meanwhile, about 100 invited guests celebrated the opening of the sculpture upstairs in The Cloud overlooking the house.
Parekowhai was not present.
Mayor Phil Goff also stayed away.
Former Auckland deputy mayor Penny Hulse told guests the sculpture "is doing what public art does - it provides a place to stimulate debate".
The head of Auckland University's Elam School of Fine Arts, Dr Peter Shane, said the work was "the most significant contemporary public art work in Australasia".
"This sculpture is no more a house than the sculpture of Sir Dove-Myer Robinson is a man.
"This is art," he said.
"It challenges and provokes and it offers different ways of thinking about it.
"It doesn't determine what our response is. It simply offers different responses."
Lights inside the house, symbolising the stars of Matariki and the welcoming light of a house at the end of a journey, are being switched on at dusk.