if a majority of the members want snacks to be provided a majority should be willing to share the responsibilty
there are a number of ways to (pass around the responsibility)
you could pass out numbers as people come through the door- then with the guild calendar in hand randomly draw numbers from a hat- whom ever has the corresponding number would be written down for that meeting- ect until the calendar is filled- then reminders would need to be sent out - maybe in the newsletter/agenda - the secretary would probably be responsible for that- if anyone had a problem-could not participate she could let (whom ever) know so a new number could be drawn to replace her month....there are lots of different ways to deal with it- or if not that many people care about snacks- forget about them-