When a user who does not have access clicks a link to a restricted page, they get a message like, "You cannot view this page - Page level restrictions have been applied that limit access to this page."

It would be better to add something like "See <the Confluence Administrator *or* UserName> if you think you should have access."

UserName would be set in the page restrictions dialog.

Besides giving a user some direction when they think they need access, the field would help the Confluence Admin keep track of who requested and is presumably in charge of restrictions for a page.