Final answer:
Unwrapped table settings should be cleaned and sanitized even if they appear unused to prevent cross-contamination and ensure the safety of future guests.
Step-by-step explanation:
After the guests leave, unwrapped table settings do need to be cleaned and sanitized even if they were not used. The health and safety regulations typically require that all tableware, including plates, glasses, and utensils, that have been potentially contaminated, must be thoroughly cleaned and sanitized before being used by another guest. This is to ensure that no cross-contamination occurs, which could lead to foodborne illnesses. Therefore, even if table settings appear untouched, they may have come into contact with airborne particles, aerosols from sneezing or coughing, or have been handled by guests or staff, which necessitates proper sanitation.