Upvote:4
The rebels have to rely on volunteer force.
The government has laws regulating conscription; people who evade conscription face a prison penalty (or in extreme cases a death penalty). Thus normal people with families and their place in the society, have no choice but to serve their time in the military, even if they don't support the contemporary government stance or don't support the war. Those are the normal people that if ordered to shoot at the "enemy", always overshoot and don't kill anyone. This sensible behavior was estimated in later time and different country to occur with 70%-90% of infantry soldiers.
If the rebels could gather 50% as much as government, it indicates to me that the rebel cause was exceptionally popular.