More than 40 protesters held an hour-long working conditions "teach-in" outside the Burger King outlet at Aotea Square in Auckland yesterday.
After the speeches, two protesters tried to enter the store but found the door blocked by security guards.
The Unite union national director, Mike Treen, said the protest was to speak up for the company's workers about a culture of exploitation over pay and individuals being intimidated not to join the union.
Three-quarters of the staff were migrants and students and a series of teach-ins around the country would show support for "young, vulnerable workers".
Burger King NZ was resisting signing a collective agreement with the union and was the last major fast-food chain without one, he said.
The union is taking the company to the Employment Relations Authority, but Burger King's marketing director, Rachael Allison, said last night that the proceedings related to union membership and did not mention any allegations of exploitation.
"If employees or the union raise issues with us, they will be thoroughly investigated."By Wayne Thompson Email Wayne