Big life events are always worth a visit if you get invited, and you always learn something from the mix of people who attend. Whether it's a funeral, wedding, baptism, and so on.

Does this person have friends from childhood? Do his friends come from the same place, or all sorts of places? Do they know each other, or does he have a lot of singletons there?

Who considers themselves close family? Second cousins? Or did their cousins not even come?

How well represented are various social classes?

I always find these things super interesting when I go to one of these.