Pretty much anyone knows that government has access to your location data, however did you know that private individuals, for profit companies and other organizations do as well? The answer is simple. Your cell phone company sells the data and they buy it.
Police departments have also been able to obtain your location without needing a warrant. Why bother when they can just buy the information?
The sale of location data has become a hot business as smartphones have proliferated and technology for gleaning their whereabouts has become more precise. The information is valuable to marketers, police departments and even investment firms because it can provide revealing details about people’s daily lives, such as where they live, what shops they frequent and what doctors they visit.
https://www.nytimes.com/2020/02/28/technology/fcc-cellphones-location-data-fines.html
If the carriers are prevented from doing this the next move is that the buyers will just buy the data from the apps installed on your phone. It is also well known that the publishers of the apps (and tech companies) are also selling this data.
