The social committee would advise people who would like to host a house party but aren't sure of the details of how to make it successful. Members of this committee may be willing to host a party on their own, but they aren't required to.
People who like to entertain don't necessarily want to host every event at their own house. But they may be willing to help another plan and execute a house party. This committee would be perfect for someone who knows how to host a successful party. Extra points if you have recipes for vegan, vegetarian or gluten-free hors d'oeurves that you are willing to share. Desirable skills are knowing how much cheese and how many crackers are necessary for the expected crowd size, how to organize a successful potluck, and where to find inexpensive utensils.
Potential hosts and hostesses would benefit by the guidance of someone more used to hosting a party for people they don't already know. Some members of this committee might choose to host at their own homes or venues, but they may just advise/assist others.