I'd argue that is it neither, but is instead so that both Apple and Google can eventually offer localized and personalized marketing dependent on the area that your phone is reporting that you are in or have been in fairly frequently. An example would be giving you a discount code for that restaurant that you have passed by 4 times in the last 2 weeks at around dinner time. This is part of my theory about why apple is building the enormous data center in NC.
I may be wrong but looking at the code and example data it seems that the Android cache only keeps track of the latest time stamp at a given cell tower so it wouldn't know the frequency of visits in an area. This is definitely a possibility for the iOS cache but I can't imagine this would bode well for the privacy-conscious folks.
I agree, but at the end of the day anyone that is that concerned about their privacy and even remotely tech savvy will be able to find a way to opt out. A friend sent me the below article about a utility for jail broken phones that can be used to get rid of the tracking data. In regards to the Google data, does it appear to you that the latest timestamps are transmitted anywhere? The way Google rolls I would speculate that they would use timestamps and location with their amazing maps resources and cloud storage to independently store all of the metrics.