Always annoys me when I want to use a WiFi scanner to determine the range of an access point in different locations for example and it needs me to turn on location access first before it can get WiFi data. The open source app doesn't have an Internet connection so there's no way for it to send back data to the mothership even if it had an SSID database baked into the apk. For me, and traditionally, the location switch is to turn on or off energy-hungry GPS hardware, not gatekeep when I trust apps to collect my location. I can set those to "only while in use", deny their Internet access, or just not install them if I don't trust them with the location permission