My perspective is the opposite. I think the more rural, and smaller the group, the more involved the community would be in wanting to find a killer of two of their own. In the bigger cities that more populated atmosphere tends to dilute that community feeling and people get an it doesn't concern me attitude more often. JMO
I think in big cities, a serial killer would need to kill more for the inhabitants to realize that indeed, there is a serial killer on the loose. In a small rural area, if a serial killer preys there, the word will get around sooner.
Big city - Seattle - and two serial killers...
With Ted Bundy, the public grew truly scared of his activities when two women were abducted from Sammamish lake in the same day. Before, Bundy abducted the same types of women, but at different places, and there was no connection between them, so for a while, the cases were not linked. Another thing that made the public aware - and scared! - was the fact that most girls were college students. A family could easily imagine their daughters being in this situation.
About the Green River Killer, I was not even aware of the case when I first moved to Pacific Northwest. And GRK actually preyed in a very narrow area, one street of SeaTac. I think the fact that he preyed on prostitutes and young runaways, "problem" girls, often with difficult family situations, made him invincible for such a long time. Prostitutes migrate, so their disappearance was not registered for a while, and also, it might have given other women a false sense of security.
Now, in Delphi, a rural area, two girls were killed, and it is a huge case. Moreover, there is a question whether Flora, and even Evanston, cases, might be related.
Reading through Bundy's case, I am now wondering if the BG guy had a longer history, but if indeed, his preys were different and are not seemingly connected.
The Bundy's victims were connected in that they reminded him of his first love, a student at UW, who rejected him.
GRK was also driven by revenge, as he visited prostitutes during his service time and it probably ruined his first marriage.
I think this person, the BG, might have a certain victims list, but no one connects them, either, because the principle of selection is not obvious. He has a car, if he killed before, it was probably far away from Delphi, and if there is indeed something that connects his victims, maybe it is his revenge?
MOO - what if the connecting factor is age, high-middle schoolers? He did not touch a single hiker, a woman walking alone. And attacked teenagers.
Possibly he viewed them as middle/high schoolers, girls and boys, who once rejected his friendship? Reminding him of the kids he hated at school? Someone bullying him?
I think his victims would not be around Delphi. But I wonder if they would be around the same age as the girls. And of both sexes?
MOO. Just an idea.