I agree government should be constrained. That said, while government may not be the only thing keeping you from murdering people, other reasons are not shared across the whole of society. We don't all organize around your religion or moral code, let's say, and because of that, we have government.

It's true that government as a group of representatives of all people is slightly different from the now self-aware monster the (U.S., insert-your-personally-experienced-representative-government-here) government has become. But it's still the single organization we all agree to work through, and so changes made across an entire society most likely have to go through that government.