the thing is that not everyone is friends with everyone and this is not targeted to her specifically, nor is it a complaint. Not everyone has their posts set to "Public" and therefore, those who are not friends with each other may not be able to see all/any posts.
This section is made so that you can easily share your links for this event with everyone else in one place. There is a chance that less people will click on your posts if they are not posted in groups or if they don't appear on their feed right away. So then, imagine if everyone posted one link but said that the rest were on their wall; it would defeat the purpose.
We Admins are just trying to keep it as simple but as helpful for group members as possible.