Hi, welcome to GTA Wiki. Thanks for contributing to the Restricted Areas page, and for taking interest in the wiki. Please leave a message on my talk page if I can help with anything, or as alternatives, leave a post on a forum, or refer to the Help pages. -- Ilan xd (Talk) 18:35, April 21, 2012
The wikia bot sent you the welcome message, it just uses the name of the the latest active admin.
As for the Shoreside Vale mountain -- I'm not sure, but this is how Rockstar Games did the game. Maybe they did this because they don't want the players will get out the area, or something similar...who knows?