It makes the car stinky, for one ... My MIL used to smoke & drive all the time, but quit when it became obvious that it actually contributed to deterioration of the inside of the car.
I've never seen a pic of MK smoking before - is this a new development or has she smoked for a long time?
Yeah I'm not seeing the big deal about this either (other than it's bad for your health). Every smoker I know smokes while they drive (I used to do it when I smoked).