Unenforced laws can be an attempt to persuade without punishment. Sometimes it can be that the enforcement of a law is to tedious, in my country (Belgium...) for example it is mandatory to vote, but so many people don't that only some get punishment by some kind of lottery.
We also have some very weird local laws (called GAS) that for example forbid children to play without ensurance and state permission, or forbid you to sing out of tune and other crazy stuff, you can get away with some of them if you are lucky...