During the campaigns so called "Lost Vehicles" appear. During a mission I placed some troops in a building next to a lost Engineer truck and I somehow gained it's use. So I thought to myself great stick some troops in a building next to a lost vehicle and I get to use it. Nope this has only happened twice so far once with an engineer truck and once with a tank. I've put troops in every building near a lost vehicle before now and nothing. Is there a bug in the 3 games so this doesn't always happen?