The French love protesting. The tradition goes back to the French Revolution - when the monarchy was overthrown and a lot of people had their heads separated from the rest of them.
If its American to sue, then its French to protest. "En greve, toujours en greve".Hardly a week goes by without a "greve" "(strike action) or a protest march. Everyone joins in, placards come out. The next day everything is back to normal.
The railways and buses are particularly prone to disruption by these one-day inactions, due to strong membership of the CGT - the communist trade union. Strange ten years on beyond the collapse of communism in the East the French variety goes blithely on as though nothing had happened. Red flags, clenched fist, Che Guevara T-shirts. Observers have said France is the only example in existence of a successful communist state.
You may think as a visitor this doesn't affect you, however be warned, it is not uncommon for transport to be disrupted - air traffic controllers are known to come out in sympathy with any greivance. During the recent national demonstrations against the "CPE" first job contract, students invaded an airport runway, and the police would do nothing to remove them, so bang went all the flights. Its a right to protest.
Mostly its the Left that do the protesting, though not always. American visitors of a sensitive disposition should be warned the French Left have very slightly anti-American leanings. Supporters of President Bush who stumble on such protests might want to avert their eyes.