I doubt that they approved of it at all, but that there wasn't anything that they could do about it until the kid was legally an adult. It was a dumb move on their part however, as they may have lost their daughter forever by their action.
I also agree 100% with Al's post.
A classic case of target fixation. The bike (motorcycle) was barely leaned over and the rider could have easily avoided the bicyclists. Instead he panicked and kept looking at the bicyclists. Unfortunately for him and them, you go where you look.