Long thread about this elsewhere. Probably best to link to it, if that were allowed.

Anyways, like most all social activities and events in the US, cycling events can feature alcohol. That isn't a cycling issue, it's a societal issue.

Work party? Alcohol.
Tailgating? Alcohol.
Hanging with friends on boat? Alcohol.
Hanging with friends in a backyard? Alcohol.
At a stadium/arena for sports? Alcohol.
Watching a comedian? Alcohol.
Playing golf? Alcohol.

It's just a societal issue and not cycling specific. The author does a terrible job of tying it to cycling. She just cites examples where it's excessive in cycling due to the group dynamic and individual's inability to self regulate. That isn't unique to cycling.