I imagine you'd have to match up multiple measurements to get an accurate count. A busy happy hour will throw off your numbers because you'll have 20 people sitting but 50 more standing who won't be counted.
Are you interested in just the number of people in the restaurant? Or, more importantly, how many people are ordering food? Because you could have a table of four share a $10 appetizer and you'd count 4 people.
Are you interested in just the number of people in the restaurant? Or, more importantly, how many people are ordering food? Because you could have a table of four share a $10 appetizer and you'd count 4 people.