What is a common physical sign of intoxication that can be observed in a customer?

Bloodshot eyes are a well-documented physical sign of intoxication that can be readily observed in customers. When individuals consume alcohol, it can cause the blood vessels in the eyes to dilate, resulting in a red or bloodshot appearance. This physiological reaction is one of the first noticeable signs of overconsumption and can indicate a person's level of impairment.

In contrast, a well-groomed appearance typically signifies that a person has taken care of their hygiene and presentation, which has no direct correlation with alcohol consumption. Improved posture is often associated with being more alert and aware, which is usually not the case for someone who is intoxicated. Similarly, a high energy level might suggest an individual is feeling lively, but it doesn't reliably indicate their level of sobriety, as alcohol affects individuals in various ways. Thus, bloodshot eyes are a more reliable indicator of intoxication that staff should be trained to recognize.