The van was apparently running and in gear (and unattended). We already have laws that make it an offence to leave the keys in the ignition of an unattended vehicle, and presumably in order to remove the keys you need to put the vehicle in "Park".
Of course, if the van had traveled through the perimeter fence it would have been in the City of Toronto, where a bylaw makes it illegal to leave an engine idling even if the driver is inside.
