I alwayse check this before downloading apps because i dont want apps to spy on me. And what i noticed in practise is that usualy payd apps offten dont collect any data and even if they do its less data than free apps.
So obviusly they collect that data to sell it and to make money that way. And if you think only big companies for advertising buy that data you are wrong.
Gowermants, secret organizacions and milioners who want to control your life is bying that data the most.
Not all do you even know what open source software is? Its when whole programs writen in programing language is publicly available. So for those programs we dont beleave the devs to self report corectly. We see for ourselfs what kind of code is inthere and does it colect some data or not…
Also here in app store you can see that google apps colect a lot of data while some other apps dont collect data at all… So its not usless, meaby its not perfect but its better than nothing…