They do serve a normative aim, i.e., 'we should have drivable two-way roads', yes. I'm not sure we need to reduce all norms to 'morality'. But if we think of m

They do serve a normative aim, i.e., 'we should have drivable two-way roads', yes. I'm not sure we need to reduce all norms to 'morality'. But if we think of morality in a really broad way, like 'humans (or other sapient creatures) seeking to satisfy preferences or impose additional structure on nature or society for their own purposes in a universalizable/principled (i.e., fair) way', then definitely: laws should always be motivated in some way by morality. That's different from the claim (which I'm not saying you've made) that this relationship means that laws should always simply 'encode' moral norms in some direct sense, which imo is a common (and mistaken) simplification. But yeah I think we're on the same page.