I always wondered how it would handle lesser known systems, like the SSID "Train's on-board WiFi" (Dutch: "WiFi in de trein") that we have in the Netherlands. There are not a million trains, but they do appear in a million places. Like with airlines, I'd think they notice, or have a script to detect, "oh we have a bunch of locations many kilometers apart" and then remove them, but since I don't use WiFi location services (I don't agree to share my location with Google 24/7) I don't actually know.