From what I can tell on the videos, the goal is to get them to five or six feet long. At that point, they're pretty unstable and usually leaking leftover beer all over the place. It's entertaining, and far from the worst thing that's happened in the bleachers, but I get the Cubs not being huge fans. The other problem is fans sitting a few rows away start throwing their cups towards where the snake is forming so they can add on. Don't really like fans throwing things in general.