The message of the protesters is lost, or at least greatly obscured, by the actions of the destructive few. The protests are about improving the civility of society. Arson and looting works against that.
Also, if military surveillance is going to be used, the footage should apply to identification of any and all criminal activity, including that of police officers acting in violation of their role to serve and protect (making the potentially incorrect assumption that they're meant to be serving and protecting a civil society).
How much good grace would be earned if the military surveillance was used to prosecute police brutality and misuse of authority in addition to arson and looting?