Because legislators now imagine themselves to be prognosticators, so they want to proactively outlaw that which they see causing problems in the future. Since talking to others also distracts the driver, we should soon see legislation permitting only one person per vehicle. Oh, and kids distract, too. Sorry, mom, no more rides for the kiddies. If they can't walk or ride their bikes, they don't need to go. Then we need to outlaw drivers under 30. Those damn kids drive too fast and don't follow the rules of the road.
