In terms of popularity, what hobby compares to being a sports fan
When you're among 60,000 of your closest friends, your accountability diminishes. It's very different than if you're at a bar with 10 people.
Fans are relatively resilient in coping with loss. If we weren't, there would be no Cubs fans.
If other fans communicated when something isn't appropriate that would curb the behavior. Many fans don't want to get involved.