Isso é abordado na romancização oficial do filme. Era para ser uma ocasião memorável que a hierarquia da operação (assim como os Stormtroopers) pudessem falar no bebedouro mais tarde.
Além disso, Hux parece gostar bastante da coisa toda e, vamos encarar, ele é o chefe e pode agendar o que bem lhe agrada:
The mass rally was impressive. Those who were present would never forget it. Which is the point of such things.
A thousand or so stormtroopers and their officers fronted assembled TIE fighters and lesser machines of war. Around them rose the central edifices of Starkiller Base. Towering still higher above the buildings were the snowy crags of the surrounding mountain range that simultaneously shut off and shielded the central portion of the base from the world around it.
Glorying in the moment, General Hux stood at the head of the assembly flanked by his senior officers, all aligned atop a raised platform backed by an enormous crimson-and-black banner stamped with the insignia of the First Order. Enhanced by artfully concealed amplification, his voice boomed across the troops assembled on the parade ground.