They do. It can be expressed through many different means but the end result is the same: people want to exert control over each other, especially people they consider “their own”. Having a representative legislature with members on equal footing is a bulwark against this. Which is why in the absence of consensus the consensus is to do nothing at all.

> And the rules in your state affect me living in my state quite a bit.

So two things about this: you’re not exactly wrong, but as far as humanity goes: the Earth is a closed system which means as far as we go there’s no limit to this line of thought except those we impose upon ourselves. Recognizable borders are a compromise, even internal ones.

What I do might affect you, and things my State does might change conditions in your State in the abstract, but in the absence of a damages claim or a legitimate grievance, we are not automatically entitled to effect the lives of others as we see fit. Which is why we have representative legislatures and governments: these are chambers and actors which are vested with powers to negotiate amongst themselves on behalf of their constituents and diplomatically engage with other governments.