COSATU members sub-contracted to transport companies RTT, Transman and Capital protested yesterday outside the offices of Edcon in Isipingo near Durban.
The protesters were calling for a ban on labour brokers.
The protest, one of many that took place all over the world to mark World Day for Decent Work, was organised by the International Trade Union Confederation.
The protesters complained that they were treated like slaves and vowed to outlaw labour brokers. They also demanded pay increases because they were paid "peanuts".
Many held up placards, one of which said: "Decent work for all. Stop slavery. Ban labour brokers."
One protester, who claimed to be a "permanent casual" because of labour brokers, asked: "How can a person work for a company for more than five years without being made permanent. Our wage is R1600 but R1100 of this goes to the agent and we only get R500."
Sydney Zulu, who says he has been working on contract for the past 12 years, said all the protesters wanted was to be permanently employed.
"We are only standing up for our rights because this problem will not go away if we do not take it on. We have families to take care of," he said.
Sizwe Mpungose said: "We don't want labour brokers at all as they exploit us. The terms of our employment are that we are only liable to them for three months. Thereafter the company should employ us permanently."
"Cosatu's position on labour brokers is clear, but a final decision on the issue has to be made by Parliament," said Cosatu spokesperson Patrick Craven.