You are falsely conflating so many things. I highly doubt your local law prevents certain people from ever accessing porn or gambling, because its absurd to enforce. More likely is that they forbid use of employer information system to access vices, which is fine.

Secondly, your local municipality isn't forcing you to access Facebook just because they put some content there.

Third, if you feel that strongly about this then go to your city counsel and demand they put their content somewhere else.