HitP is only really that busy during the week break between Christmas and New Year, when everyone is off work and school. Considering how the park is not very full the other 95% of the time, i'm not sure it'd be worth it from the park's perspective to staff and maintain another large section of the park when it'd sit almost completely empty during the rest of the event. Plus, I'm pretty sure Toro is very temperamental in the cold, Ka is notoriously unstable even in optimal conditions, and Zu would not be fun that high up in the cold. 3/4 major rides closed, leaving a very empty area of the park.