Originating in 1994, the "Feast of Maximum Occupancy" is an annual gathering held in the city of Richmond Heights, Missouri between the Ides of March and St. Patrick's Day, or on the nearest Saturday to St. Patrick's Day. The stated goal is to gather as many persons into the building as possible, hence "maximum occupancy", though it is believed the event originated as a celebration of achieving maximum roommate occupancy and hence lowering rent payments to the smallest possible amount.
Fear Of Missing Out - a pychological condition which leads to participation in events one wouldn't or couldn't normally participate, in (an effort) to acheive bragging rights, or which prevents an individual acting normal in the presence of such an event in case they are invited in by one of the acting parties. Bragging rights are often misjudged at the time of the decision.
Gary went with Julia and Tom into a bedroom at a party to have a threesome, even though Gary doesn't like men, because he was gripped by FOMO. Gary still hasn't spoken about the experience.
Peter couldn't look away from 2 drunk girls making out even though a pretty girl was talking to him. The FOMO was too strong.