Do you have to share your location with it? I don't use it but similar apps like Instagram don't have my location permission.
Even without location they can get a pretty good idea of your location from your IP address or any other signals. Their neighbor also might have allowed access to their phonebook or something like that to make the connection obvious.
Wifi ssids around you might be enough.
Even without location they can get a pretty good idea of your location from your IP address or any other signals. Their neighbor also might have allowed access to their phonebook or something like that to make the connection obvious.