One of Ben's key traits is that he's a believer. Him and Sammy are the classic believer/non-believer ghost hunting duo, but Ben believes in more than apparitions and werewolves and curses. This is a man who cites his "heart stats" over actual evidence. He believes King Falls is the "best small town in America," he believes the Tim Jensen who comes back is his Tim Jensen, he believes Cecil and Herschel will always be best friends even when they have month long falling outs. From the first episode, barely knowing Sammy, he just trusts that they're friends. Think about how quickly they go from strangers to best friends to brothers, just because Ben was willing to believe in both what Sammy had to say and believe in Sammy himself. Now picture what it's like for Sammy, who's listened to this guy who will believe in anything, for better or worse, go on about aliens and lake monsters and haunted forests, to read the words "Who is Sammy Stevens?" Picture what it felt like, for a guy who tried so hard to leave his past behind him and could only move on because he had such a supportive, loyal, and faithful best friend, to see those words. The first thing Sammy hears Ben doubt is him, the first thing he distrusts is his own best friend. Picture how that hurt. The world's truest believer only doubting you.
