I fully understand your point, and it is indeed a problem. In fact I have personally called out other apps for this: https://www.washingtonpost.com/news/capital-weather-gang/wp/...

Thing is, possibly as a result, Apple blocked ARP access in iOS 11. You can no longer get the BSSID and use that to get user location. Because the post indicates he used an iOS 11 device, this leads me to believe the coordinates were also not obtained with Wi-Fi information.