I’m amazed you would overhear any conversation. Whenever we find out conversation stops when the waiter approaches the table. It isn’t planned it just happens.
As I moved about my section I listened carefully to the chatter at my tables, listening for clues about my customers that would help me give them better service. Good service meant better tips and I wasn’t there for fun! I also over time noticed trends in demographics and tipping. It was an interesting experience.