I know what you mean.
The plan to get around that is to make things mission based. I know convoys of soldiers aren't ever sitting around waiting for a single soldier to eat, sleep and use the restroom before they reinforce the frontlines, but this is still a game, and the focus needs to be entertaining the player. I was thinking that your encampment would be hit by a few geurilla attacks throughout the game after the player heals themselves in the infirmary or something to spice things up. But I don't know how to make everything realistic while still making a playable game.