Unfamiliar places could be more dangerous than familiar places, unexpectedly. The boy had been discovering that an unfamiliar place was more easily "haunted" than a familiar place simply because there was less there to distract the memory.
The quote highlights the idea that unfamiliar environments can invoke a sense of danger that familiar ones do not. The boy realizes that when he is in a new place, his mind is more susceptible to fear and anxiety because there are fewer memories tied to that location. This lack of distraction makes it easier for his imagination to conjure up haunting thoughts.
This notion suggests that our familiarity with a place can provide a sense of safety and comfort, while unfamiliarity can lead to vulnerability. The absence of recognizable landmarks and memories allows the mind to fill the void with ominous feelings, creating a haunting atmosphere in unfamiliar settings.
