Since crypto-anarchy & free-market economic anarchy both do away with centralized authorities isn't this sort of behaviour what is *expected* of members of the community under these systems? Doesn't the fact that there is a clear and present danger to both person and community justify these sorts of actions?

The concept of "Free-Market-Crypto-Anarchy" doesn't jibe with the "Lynch-Mob Democracy" mentality exhibited by Gates. One of the fundamental principles of anarchy is a willingness to let others hash out their own problems, i.e. I will ignore him unless his actions impact or affect me personally/financially. It is not as if the Gates were going to be affected by the "suspects"...they had to go out of their way to interfere with someone else's pursuit of happiness. That is clearly unacceptable. The last thing we need is a deputized citizenry...talk about a police state. (I guess that would be the ultimate form of the "Policeman Inside")