The data was stored on the phone, not sent to Apple, and certainly not to advertisers.
The data was used for GPS assistance -- it was a cache that triangulated your location from cell phone towers to help get a faster GPS lock (and to find your location without GPS if you’re getting bad GPS signal).
If you're concerned about the police finding out your moves, they have access to such information from the tellcos themselves with your cell number, whereas to use those stored GPS logs they would need physical access to your iPhone.
The data was used for GPS assistance -- it was a cache that triangulated your location from cell phone towers to help get a faster GPS lock (and to find your location without GPS if you’re getting bad GPS signal).
If you're concerned about the police finding out your moves, they have access to such information from the tellcos themselves with your cell number, whereas to use those stored GPS logs they would need physical access to your iPhone.