I am not quite so sure about this. Please consider the following:
If someone said, "ok, say cheese," I might be inclined to remove a cigarette from my mouth a)not to be rude, b)to offer the most flattering pose of myself and c)to make the gesture I might choose to make (let's say opening my arms wide in celebrating the moment as the gentleman did in the original photo).
To take it further, my dad has smoked since I was a child and I know from his habits the following:
Generally, there are a few ways to remove a cigarette from your mouth to expell smoke OR to preserve the cigarette mid smoke. If my father is mid smoke and is in a place that allows open smoking, he puts it in between his index and second finger, and arches his hand away from his body at the elbow and holds the cigarette at his side in this position. (To discard it, he would toss it to the ground, stomp it out and pick up the filter).
If he is smoking is a situation that calls for more discretion (in front of family members who oppose smoking, etc.) He will instead turn his body a bit and when he is finished, will clip it at the filter in between fleshy part of his thumb and index finger, careful to clip it in such a way not to burn his fingers. I argue, it is this second method that was utilized by the man in the photo.
I do not believe the cigarette was lit. My theory is that the man rolled one up and was about to smoke when the photo was announced. He clipped it in his hand to essentially hide it (not that he felt it was that important, but seems like a natural gesture).
On that point, I am often holding souvenir bags in photos taken while I am on vacation. I have noticed that if someone else is in the photo with me, I will always place the hand with the bag behind the other person to hide the bag from the photo. It is not conscious, but I always do it.
Now, consider this evidence. Because I am a dork..cough, I mean law student, and a common technique at trials is reenactment, I took the liberty of rolling a fake (I detest the idea of smoking) old style cigarette using a random piece of paper. I put in between my lips. When I clipped it in between the fleshy part of my thumb and index finger and pulled it from my body to open my arms, this is what I saw when I looked down:
Case closed? Try it yourself and let me know.
Joe