Imagine if you got the meet someone that you have admired for years and based your whole career largely around everything they did. Imagine that this person was cool as hell in person and the relief you feel from them not being lame. Then imagine that this person asked you to do that thing you've been getting good your whole career for them!
Moments like these are special because most of us honestly will never experience them, at least not checking off all those boxes. You can't help but smile when you see something like this.