When I walk into a casual restaurant or grill, I might look at the way the chairs are arranged around a table, or, if the table has not been cleared from  the previous diners, I’ll look at how they left the table. I’ll consider whether the previous party met for a business lunch or had a more intimate kind of conversation? Were they in a hurry or did they linger? Were they old friends or regular customers? Did they split the check, share food, or tip well?