In the war of the five kings, the Lannisters don’t use the authority of the crown to call upon the various kingdoms to fight for them, like the Vale and half the Stormlands etc that sit idle. While they have obvious reasons to expect they won’t answer the call, shouldn’t these people be anxious that they’re committing treason by not fighting for their lawful leader? It seems to be treated like a war between the Lannisters and the Starks/Riverlands, not the Crown at all.