Philly, as like any major city, has good pockets, great pockets, and bad pockets. Philadelphia by name encompasses a very large area. My aunt lives in NE section of Philadelphia; literal 5 minute drive to Bucks County. If she gets on the highway and drives South for 30 minutes at 60mph, she's still in Philadelphia. But yes, there's parts of Philadelphia I might not drive through during the day. There's also parts that have million dollar houses.
These murders happened in Bucks County, which has varying classes of ppl throughout it. Bensalem, which I believe may be the largest town in the county, has parts that are middle/low, middle, and upper/middle. You can rent an apartment for $1100, buy a townhouse (row home) for $400k, or a single family for $700k and all the prices in between. Solebury, where the bodies were found, is more affluent upper/middle and above.
Pulling a story from Philadelphia and wondering if it were linked through natural assumption would be equivalent to a crime being committed on 100th St and wondering if it were related a similar crime on 1st St (analogy).
I think these murders have brought hardship to so many things outside of just the crimes. Families, friends, towns, communities, and businesses. I'm sure I'm more sensitive to these things being from Bucks - knowing ppl that knew both victims and perpetrator.
I also think, and I am very guilty of this, is that with the shocking nature and randomness of these crimes we want to possibly believe there's a bigger picture. So we want to find the links and almost grasp at the tiniest thing because there has to be an explanation.