* The show is edited: Reality TV is edited for entertainment. The cast's sleep schedules are likely condensed or exaggerated for dramatic effect.
* Individual differences: The cast members are individuals with different sleep habits and preferences. Some might stay up later than others.
* The show's theme: The Jersey Shore was known for its party atmosphere, so sleep was probably not a high priority.
Instead of focusing on a specific bedtime, think about the show's overall theme and how that might influence the cast's sleep habits.