It's like one big sloppy family reunion
There's an incredible feeling of camaraderie around Denver during the festival. Sure, it helps that everyone has an elevated blood alcohol level for three days straight, but brewers are a delightful lot of people, and they really seem to like one another.
You'll see them greet one another like people at a family reunion. And it's not just the brewers -- everyone attending is a huge beer fan, and some have traveled a long way to be there. I'm not a hippie (full disclosure: I have attended more than five Phish shows), but there's something about being in a place where everyone there wants to be there. It's a place you want to hang out in. If you're not in a good mood when you get there, you'll surely be in one when you leave.
The city of Denver basically turns into one big party
GABF is open for 4.5 hours each day for three straight days. The city of Denver, however, is drinking craft beer the entire week, and for nearly 24 hours a day. Even breweries that aren't going to be at the fest are throwing parties all over the city -- this year, 3 Floyds is pouring four of its beers at a Denver brewery. Tap takeovers are the rule, not the exception. Beer-pairing dinners abound.