They are impervious to reason or argument. Never mind national parks or their traditional owners, this is a symbol of their absolute power. However, this is also the classic struggle for the hearts and minds of the people. By demanding proof of identity and intent from motorists, the dissenters will harden the hearts and close the minds. The Age is right.
Misguided tactics damage a good cause.
It is always difficult to confront an obdurate government over an issue on which it does not need your cooperation. It can ignore you. A government cannot ignore those who deliberately flout unjust laws, such as those who refuse to cooperate with military conscription. Then, the government and the citizen come face to face in a battle between conscience and law. Such confrontations are dramatic, simple and viscerally satisfying.