Sadly, all the monsters and ghouls go back to being normal, everyday, run-of-the-mill, real-life, monstrous bullies such as bullheaded bosses and leaders and actual ghoulish, grisly serial killers and terrorists. They exact a lot of mean, petty, and outright horrific actions on subordinates, constituents, or unsuspecting victims.
The silver lining to this duly depressing predicament is that fairy godmothers, firefighters, nurses, maids, and other seasonal characters who are forces for good also return to their day jobs. Hopefully they'll limit or halt these monsters and ghouls until next year. Because as we know, on that one night, all bets are off. No one holds anyone in check. There's a time honored sanction to be who and what you desire with no holds barred. ; )