You could create a List of needed Items. i.e. Volley ball net, Plates, Charcoal etc.
You can do this on Evite. It is a very handy tool. You basically build a drop down menu for the RSVPing member to choose from. It would be listed in their RSVP response in addition to any comments. I think this woud cut down on the # of Comments and also I find the Questions to be useless!!!!