Neither of the guilds I belong to do snacks. One meets at a LQS so I don't think snacks have ever been discussed. The big guild has a 'social' period from 6:30 - 7, and the program starts at 7. I think there an ice-cream social in the summer and a holiday party in December. For our all-day workshops, we brown bag it. Works quite well.
Cheers, K