<human>: This happened a few weeks ago.  I was sitting outside a sushi restaurant with my party waiting for our table.  I was facing the restaurant which was a glass window.  As I looked inside I saw a guy with a red fedora and a feather sticking out sitting down facing away from the window.  I thought it would be a good opportunity to make my friends laugh so I started to rip on this guy's fedora.  After a few jokes one of my friends asked "what kind of loser wears a fedora anyway?" to which I responded "HAHA this guy right here!" and I pointed at the guy through the window.  Almost immediately the guy sitting across from me in front of the window facing me said "Wow, just... fuck you" and he looked really insulted.  I thought it was hilarious that he was defending the fedora wearing guy with such vigor so I said "Fuck me? Fuck ME?!? Nah man, fuck this guy!" and I pointed back at the guy with the fedora.  All my friends laughed and Mr. angry pants just looked upset.  A few minutes pass and they call his name so he gets up and goes inside to his table.  Then I realized he had no idea there was even a guy with a fedora behind him through the glass.  He must have thought I was just pointing at him saying he was the kind of loser that would wear a wack-ass fedora.

Can you give me the gist of the text in a nutshell?
<bot>: made fun of a guy's fedora behind his back and everyone laughed, different guy thought I was talking about him, ruined his day