[She had to truly consider his question. Her previous response, while a genuine question, wasn't entirely one she thought of besides in passing.] Perhaps take them onto one of the patrol routes, proper. Certain times of the day are prone to attacks on the walls from the predators that feast on the monster crabs. To know such a risk and having to prepare for them, even if nothing happens, would certainly warrant those who are serious and those who are not.
ooc: sorry for the delay, I've had literally no chance to tag in days