Indeed, authoritarian regimes like arbitrary laws that they can enforce selectively. As long as people fly under the radar, the laws won't be enforced. This makes sure that there will be no protests, because "who cares about laws that aren't enforced anyway?".

On the other hand, police officers (and higher authorities) can use these to lock up people that they don't like, or didn't pay their bribes. It will also mark the accused a social stigma, even though everyone and their brother violates that law, but people arrested for it are "criminals": Very effective in locking someone out of positions of power.

This can concern copyright laws, traffic laws, tax laws, laws with respect to sexual conduct, and so on... they've all been used in this way.