as just because France decides it will impose a local law doesn't mean it will apply. EU law may say something completely different
racedo, FWIW EU law is now quite clear, as captplaystation has rightly pointed out:
The new laws which came into effect around the beginning of this year/end of last year (depending on the country in question) state that social charges must be paid in the country of "base".
For once the French courts seem to be quite happy to toe the EU line (call me a cynic but I suspect that is probably because in this case it suits the French state to do so)