However that's not the only use case for android.permission.INTERNET - you need it for anything that does networking on the internet, such as API calls to your web application.
Yesterday adobe pdf viewer tell me that an update was available both on my mac and pc! So without asking my permission, this computer application (and many others) are querying the web...
You give your permission when you install it with auto-update enabled. I always disable auto-update.
A lot of people get upset at PC programs that do things like query for updates without permission.