Holds and kills let you set aside seats for production, artists, and VIPs directly on the seat map, and kill seats that should never go on sale. Hold names show right on the map, so anyone working the show can see at a glance why a seat is unavailable.
This matters at the door and in the box office. When holds and kills live on the same map everyone is working from, your team avoids selling a seat meant for crew or a comp, and avoids the scramble of tracking holds in a separate spreadsheet.