Well, in doing that he just established something very much like his own government. It is now, as a matter of practice, against Biff's law for me to write things that Biff doesn't like. The penalty is severe, enforcement fairly certain (at least within this jurisdiction). And who's going to stop him? Certainly not me; I'm smaller and less violent than he is.
But Biff isn't really the biggest problem in this no-government world anyway. The real problem is a really greedy, heavily armed guy--we'll call him Frank--who has learned that if he steals money and then hires enough muscle with his ill-gotten gains, he can demand goods and services from every business in town, take anything he wants, and make almost anybody do whatever he says. And since there's no authority higher than Frank that can make him stop what he's doing, this jerk just literally created his own government--what political theorists refer to as a despotism, a government ruled by a despot (which is essentially just another word for a tyrant).
Some governments aren't much different from the despotism I just described. In North Korea, for example, Kim Jong-il technically inherited his army instead of hiring it--but the principle is the same. What Kim Jong-il wants, Kim Jong-il gets. It's the same system Frank used, but on a larger scale.
If we don't want Frank (or Kim Jong-il) in charge, we have to all get together and agree to do something to prevent them from taking over. And that agreement itself is a government.
In other words: The reason we need...