Kids should know not to listen to people who ask for directions, need help finding a pet or say that their parents are in trouble. If the person really needs help, they'll ask another adult.
It's not only reckless but it's frightening, if you think about somebody giving your address and somebody entering your home. In this particular case we had two teens, 11 and 15 years old, at home and it frightened those two kids to the point where they went to a back room.