JMO...
In a typical sleepy small town such as Delphi, and I have spent large quantities of time in a similar sized sleepy small town in another mid-western state, I really don't believe a double homicide would be at the top of anyone's list, or even on their radar, because the mentality (at least among the small town residents I know) is "oh, that kind of stuff never happens here. Maybe in larger cities, but not here!" These communities still have their innocence. My personal experience has been that they don't lock their doors at night, they wave to each other driving down the street, they say hello and ask how you're doing when you pass by on the sidewalk, they let their children ride their bikes across town unsupervised to go to the community pool ('town' is about one square mile), they let the grade school and middle school kids run under the bleachers and around the unlit green space next to the US route that runs through town during the high school Friday night football games. Small town residents just have a completely different experience and outlook than residents of larger areas. I've always been afraid there would be a child abduction/rape/murder in the town I'm familiar with and it would devastate them the way I'm sure the murders of Abby and Libby have impacted the residents of Delphi. I wouldn't think any member of either Abby or Libby's family would influence the decision to call off the search. The footage I recall from the night the girls were missing showed the family members who were interviewed to be very concerned and worried about the girls being gone. If the families of the girls are like the families I know from my own experience, they wouldn't be critical about LE calling off the search because neither the families nor LE would have thought a double homicide possible.
JMO.
