Lilygran The Singapore chewing gum law was brought in because of the nastiness of old gum on the pavements and the expense of cleaning it off. Frankly, I should like to see such a law here. However, it actually resulted in there being chewing gum smugglers! That law no longer exists in Singapore.
It depends how you talk about Christianity – or any other religion – to a work colleague. Evangelism in the workplace is not and shouldn't be acceptable.
France has indeed introduced what are clearly anti-Muslim laws however much they try to disguise the fact. But it is the niqab not the headscarf that's the issue.
Most secular laws are concerned with the good of society: anti theft, rape, assault, murder, fraud, etc; pro education, healthcare, traffic safety etc. There don't seem to be secular laws about when you may copulate (expect to protect children), what foodstuffs you can eat, when you can eat them, etc.