I'm not going to wait to get caught up before answering these, so I hope they aren't real out of place wherever they fall.
I haven't heard/seen LE say that pings brought them out there, but I thought they had denied that it was the case. I know they said something about reading discussions on SM in relation to it, but I'm not sure now if they meant they went there because of what they read, or if they meant they were reading responses onSM to them having gone there. Sorry that's not much help.
I thought the same thing. To many people I know, a town of 1400 is almost a metropolis. As a teen, I lived in a town in Minnesota with 365 people in it. We had 5 gas stations, 2 small grocery stores, 2 bars, 1 liquor store, one supper club and a lumber yard. The town barber worked out of his house. I recently looked at a street view of the town (now almost 4k people) and most of the old houses are still there. It really surprised me when I looked at it, that I never did have any idea who lived in about 1/3 of them. If I had seen a stranger stop to talk to someone (even someone I knew), I wouldn't have thought twice about seeing the person get into the vehicle. I now live in a "big" town of almost 15000, and the same would still be true now, even if I knew the person walking and had never seen the vehicle or driver before.
I think that's slightly misleading, but not totally. I used to say that I thought you were more likely to become a victim of crime in a small town than in a big city, but I'm not sure that's still true today. I'll use an example with fairly easy numbers to work with (and made up statistics). A is a quiet town of 1000 people. On average they have 50 violent crimes a year (domestic violence, bar fights, etc.), which would be about 5000 crimes per 100,000 people. B is a city with 1,000,000 people in it. On average they have about 10,000 violent crimes reported per year (mainly deaths and severe assaults are reported), which would be about 1000 crimes per 100,000 people. Even though B has more crime, A would actually have a higher crime rate. I know my numbers are off for the number of crimes reported in most areas, but I hope it gets my point across.