It seems like the general consensus is that day guests and party guests should be courteous and understanding towards each other as to strict time frames. The day guests won't get angry at the party guests that arrive early (even 3 hours early) and take up valuable ride space before 7 pm, and party guests won't get angry at day guests who happen to be late in leaving the park due to backed-up restaurant seatings or long attraction wait times. Mutual courtesy then allows the park to stay open, rather than closing for an hour to empty the park and inconveniencing everyone.