When we get together at my house my parents tend to contribute wine, my sister a dessert and if my IL's deign to grace us with their presence they come empty handed. We tend to do the majority of the food prep but everyone helps to clear up.

My sister always has a NYE party at hers and all but one particular guest bring food and alcohol. We tend to stay over so help to clear up the next day.

We were brought up to never go empty handed to someone's home.