Thousands of people gathered for the event, which were disrupted when a man climbed onto the stage, disrupting performers.
Police officers removed him from the stage, but he resisted their attempts to arrest him, at which point his friends tried to intervene.
A violent brawl ensued, with onlookers stopping to watch and film the altercation.
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All three men involved were arrested, and charged with a string of offences.
Police were also told that the men had been ejected from a nearby store by security after creating a disturbance prior to the brawl, when one allegedly stole a traffic control light wand from an official.
The trio, aged 20, 21 and 23, were taken to Day Street Police Station and charged.
The 23-year-old man, from Wentworth Falls, was charged with assaulting police, larceny, and resisting police.
The 21-year-old man, also from Wentworth Falls, was charged with offensive behaviour and two counts of resisting police.
And the 20-year-old man, from Blackheath, was charged with assaulting police, offensive behaviour, and resisting or hindering police.
They have been granted strict conditional bail to appear in Downing Centre Local Court on January 15.