The KGB and other subversive organizations well appreciate the value of protests. They were behind the so called "peace movement" during the Viet Nam war era and had their agents on college campuses.
How the Soviet Union helped shape the modern peace Movement
Of course just as the US had almost won the war the peace movement won popular opinion by duping the average citizen which caused us to withdraw, thereby giving up literally at the point of victory!
So marches work well for subversive interests.