Final answer:
To prevent over-consumption at a bar, staff can practice responsible service, offer non-alcoholic drink options, and intervene when customers show signs of intoxication.
Step-by-step explanation:
To prevent over-consumption at a bar, the staff can take several measures. Firstly, they can practice responsible service by monitoring the alcohol intake of customers and refusing service to intoxicated individuals. They can also offer non-alcoholic drink options and encourage patrons to drink water between alcoholic beverages. Additionally, implementing policies and training staff to recognize and intervene when customers show signs of intoxication can help prevent over-consumption.