Shooting an event or crowd is like a treasure hunt. A photographer circulates, eyes open for interesting nuggets. Lighting is catch as catch can and the visual nuggets keep moving.
Sometimes you get lucky. This was back by the food table at the Creatives Pot Luck with some electric lights to camera left. The result was what my superb portrait photography teacher, Bobbi Lane, calls Rembrandt lighting. One side of the face is fully illuminated. The other is mostly dark but turned just enough into the light to catch a highlight on the cheek. The Dutch master used it a lot.