`stack.imgur.com` was created to avoid link rotting of images.

Images not uploaded with an Imgur Pro account may be [kept for only at least six months unless there is one view of that image per six months][1].

Inferring from the [Stack Exchange blog][2] and [Imgur's upgrade page][3],

 - images at `i.stack.imgur.com` should be kept forever regardless of views while
 - images at `i.imgur.com` that were not uploaded with a pro account may
   be deleted due to inactivity.

This means that anyone can upload to `stack.imgur.com` through the ![image upload][4] button (<kbd>Ctrl</kbd><kbd>G</kbd>) and keep images there forever unless they are [reported][5] or discovered to be unconnected to Stack Exchange and deleted.

My questions are:

 1. **Is this behavior expected?**
 2. Does it not matter to Stack Exchange and Imgur?
 3. Is there already an active process keeping irrelevant `i.stack.imgur.com` images out of Imgur?


  [1]: http://imgur.com/faq#long
  [2]: http://blog.stackoverflow.com/2010/08/new-image-upload-support/
  [3]: http://imgur.com/register/upgrade
  [4]: https://i.sstatic.net/aYYmD.png
  [5]: http://imgur.com/removalrequest