Society is artificial to a point. Look at the ever changing rules on what is and isn't "correct". Laws are all basically artificial. If there is a true natural law, it doesn't need to be enumerated, we would know it instinctively. If you look hard enough, there are no natural taboos; in some society everything "bad, evil, Bozo no-no" has been practiced. I stand firm on this, if someone wants to try and find some "natural law/taboo" that's never been broken, have at it. Hints, don't try to argue that any type of murder, cannibalism or incest are naturally taboo, you lose on the point that all have been practiced by past cultures some ritually and religiously.

The larger the group/society, the more rules you have. Never underestimate the power of stupid in large groups. Therefor, the need for rules. It gets interesting when rules change from group to group (e.g. driving laws, England v. the US), reinforcing the idea of artificial rules. Who is right? Does that make the other wrong?

As to competition, the Naked Survivors people prove that the smallest of groups - 2 - has competition to be top dog.