In the settings of ACL profile users there is a function - 'Post Story In Group' (Screenshot - 30.jpg)
You can do more - 'Post Story In Event' and 'Post Story In Page'
Thanks for the input on this Albert, we'll consider this in the future
Regarding this part, we actually need to switch it to those cluster (group/event/page) categories custom field setting call "stream permission", in this section we allow creator to set whether they allow member to submit story stream on the page.
These permission are created by the author of the event for each event. And the permission in the profile settings apply to all users with this profile.