I dont' believe the game models wood or other combustible building materials. Sure there are structures but I don't believe the code recognizes the fact that fire can destroy them in addition to bomb blasts and bullet damage. But, since I really have no idea about coding or computer programming in a gaming environment, I cannot be sure. I've never seen fires start in any building or structure, it's either up or down. It might be a nice addition but I would imagine that it would take some serious programming to implement that. It's a good idea but perhaps in a later edition of the game. GP bombs, historically, could penetrate 5 inches of armor plating dropped from high altitude. In WWII, a 500 lb GP bomb would flip a GV on it's back with a close proximity detonation when dropped from low to medium altitude too. That doesn't happen in the game, it's either a hit or a miss, destroyed, damaged or unaffected...most times destroyed.
Oh, we'd also need firefighters to put the fires out then wouldn't we?