It is not the lighting of the cigarette that is dangerous but driving while holding it. You cannot hold the steering wheel properly and securely while you also have a cigarette in your hand and if you drop it, because it has a hot smouldering end, you could burn yourself, your clothes or your car.
Drop a lit cigarette and you will be looking down and around for the burning fag (or trying to crush your smouldering clothes) and not concentrating on your driving.
At least if you have a phone in your hand you can drop it of an instant to put two hands on the steering wheel and really concentrate, without worrying hat it might set you or the car on fire
*International Plastic Bag Free Day* tomorrow July 3rd

