Asking for a cigarette is just a tactic to get close to their target.
Many many years ago my dad was working downtown and a young black man and his buddies approached him. One asked my dad if he had seen a wallet lying around the area because he had lost his. By the time the guy told my dad he'd just have to take dad's wallet to replace the "missing" one, dad already had a tire iron in his hand and had hit the closest of them and knocked him to the ground. (It wasn't a tire iron, really. It was the "key" that lifts manhole covers.) He then got in his work truck and called it in to dispatch. Thank God none of them had a gun, or were to slow to pull it. I loved it when dad retired!