Its partly culture. Since the days of Pétain and the Vichy occupation, the French by and large ignore govt rules and guidelines if they impact their freedoms. France had no easing in to the lockdown like we did (over a week), it was "must" and "what", not "why". Look at The attestation de déplacement dérogatoire which translates to an affidavit stating your justification for leaving your home. It does not place trust in the citizen and epitomises the state's love of form filling.
We eased in to lockdown and compliance has been substantially better than in France.