...
This is useful if you don't want to give a user access to the LUNA Library but they still want to upload content to the system. A collection administrator could collection administrator could then easily find those items by searching by owner and add them to a collection. In essence this is kind of a "lite" simple way for people to add content to the system without having to give them access to the other tools.
When you are in context of the IMIC you'll see all your items as well as other people's My Uploads items marked as public.
...