Well, yes, let's say that your flashlight app requested your location data and you agreed. You were in a park during dawn and you were looking for the stairs.

And there were like 2 ads shown to you during this 50 seconds period, while you were in the dark and not looking at your phone but using it as a duh, flashlight. And then you stopped the app to save your battery.

Do you really think some advertiser benefited by using this data?

And what "independent" ad-tech is dealing with is millions of cases above. Consistency is important. FB and GOOG have consistent data, collected over days and years, properly matched, correctly aggregated. All others are dealing with flashlight crap.