I think that people care more about the data collected when using mobile and desktop apps than websites at the moment, but that that will change. I also think that transparent analytics is a more effective way of improving your app. Transparent and anonymous means you can bring the user in to your analysis and ask them directly what the data means. More and more you see privacy policies declaring that the data collected is anonymous so companies can go further with our service and prove it. Some are already doing this, Firefox and Bower for example.
Ideally we will show the user their data in the context of the charts that the developers have setup. As Kevin said the JSON is a quick fix and you are totally correct to point out how inaccessible it might be.
Thanks for the excellent questions.