If I recall correctly, in the notes to the original board game Philippe Thibaut justified the system of having to purchase one "campaign" (basically movement and combat with one "stack"), two campaigns or unlimited campaigns in order to use your armies and navies, by arguing that in peacetime troops would mostly be quartered in barracks, perhaps with less than full mobilisation, equipment, training and supplies. If they were to be useful they would require full logistics (supply trains) and so on, which were immensely expensive. In EU2, apart from crushing rebels and natives, armies are only used during war. Navies are used for transporting also in peacetime, but the argument of being fitted for war and being fully supported would also apply. We can see that as well in the present geopolitical events. Even today, actually using your military forces, even when they are kept top-notch in peacetime, i.e. conducting a campaign, incurs enormous expenses over and above the normal military budget. The double maintenance argument seems strong. I wonder what that Swedish historian said?
