If vehicle is moving. Why would a critter not assume it is just a bigger critter?
A robot wouldn’t think a car is any different than a human if it was already shooting people and monsters.
Follow the logic. You are driving and you parked. The noise attracts the robot to you and shoots the vehicle. Why would that be odd? Even a lumbering bear would sniff your car if you were just chillin there having drove up and parked.