http://www.fanpage-boost.com/ - In the most cases non-fans are interacted on friends streams where they saw a post, meaning that a post has been liked, commented or shared by followers of the page, allowing it to show up in newsfeeds of their friends, who have not liked the page yet. Those friends have the opportunity to also like, comment or share these post, but they will not necessarily like the page as well. Especially users of mobile devices tend not to follow or explore the source of what they liked.