In the nearby village of Siderno, family and friends gave brothers Francesco and Marco Pergola a noisy send-off.
People clapped in a show of respect as the two coffins were taken to the cemetery.
Police decided the funerals could go ahead because the situation in San Luca and nearby villages did not give "particular cause for alarm".
But the usual funeral processions to the church and graveyard were banned.
The sixth victim, whose 18th birthday all the victims were celebrating the night they were killed, will be buried on Friday in Germany, where he was born.
That ceremony will be closed to all but close family members, but police said they would be present.
The men were shot dead outside a pizzeria run by Calabrians in the town of Duisburg, northwest Germany.
The Calabrian mafia is estimated to have an annual turnover of nearly $49bn - much of it from trafficking cocaine - putting it on a par with some of the largest publicly listed companies in Italy.