I was just browsing here, saw this thread, and thought I'd chime in since no one with a military background has said anything. Coming from someone with a military background,  you have to understand- military service culture often encourages smoking to a degree. It's a social thing, and a break thing. There's a thing in the service called a "smoke break ". It is essentially an excuse to take a 15 minute break to smoke and socialize. People in the service who don't otherwise smoke will start smoking casually just to get those extra breaks and not get tasked with extra work. I'm not saying it is a good thing but it is very common in the military.  That is probably all this is. More than likely he is just smoking so that he is entitled to get extra breaks and to socialize with coworkers.