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.
I don’t disbelieve you or impugn your motives. I was merely stating my experiences. But as you say you could be waiting on one table and listening to conversation at one adjacent.