Great post, @TheEmu. Really enjoyed that story. You contend that Hampton is not that special inside. I would disagree with you there. As others have noted here, the acoustics are exceptional. Many coliseums have terrible acoustics but Hampton's are nearly perfect. The scale and floor plan also contribute to the legend. The interior is designed at the perfect scale to make it feel large and intimate at the same time. And there really are no bad seats.
I'm probably biased, though. I did see my first Phish show there in 96. But before that I saw Aerosmith there in 93. I won tickets on the radio and got to go with my best friend and my Uncle to chaperone. I was 14. My Uncle found a nice seat on the balcony and told me and Mat to go wander around on the floor. He also made us promise not to tell my Mom that he had let us out of his site. With the GA floor we were able to walk right up front to enjoy the rock. Ever since then Hampton has been kinda magical for me. It's the place where parental responsibilities yield to rock! The Lack-of-Mother-ship.