Abderrahmane Saidi, 26, was at a local government office on Tuesday when he grabbed a flag and snapped the pole in two during a row with a clerk.
A July decree made insulting the tricolour an offence punishable by a fine of up to 1,500 euros.
The rule was triggered by a photo of a man wiping his bottom with the flag.
Saidi was sentenced by a court in Nice. It also gave him a four-month suspended prison sentence and ordered him to attend citizenship classes.
Frustrated by a bureaucratic delay, he not only attacked the flag but also threw the broken pole at the clerk's window, AFP news agency reports. Two police officers then restrained him, but he tried to punch them.
The Alpes-Maritimes regional authority, police and the clerk all lodged complaints about his behaviour.
The offending picture which triggered the decree won a prize in a photo contest in Nice in March.
Before the July decree it was only an offence to insult the French flag during a public event.
I'm kind of confused as to why this sort of law is even needed. It's sort of unuseful to the public safety or well being, which basically makes it the government getting pissy at detractors.