That page appears to not show what the data is used for. I wonder if it's shown elsewhere, or why apple asks for that if they don't show it anywhere. As a user

That page appears to not show what the data is used for. I wonder if it's shown elsewhere, or why apple asks for that if they don't show it anywhere. As a user, that's certainly information I'd be interested in. (Documentation lists the following purposes: Third-Party Advertising, Developer’s Advertising or Marketing, Analytics, Product Personalization, App Functionality, Other Purposes)