Don't worry about that guys. If someone doesn't want to see discussions from a group they can just leave the group. Keep on enjoying your food talk :)
st4r_lite - a shoutbox is just a box on a webpage that acts almost like a chatroom. People can come by and say 'hi' and just have a light discussion. On Custo, we have a shoutbox group that acts in the same way.
I actually think they're angry at the list of new posts (the one with all of them in all the groups), and how it's usually dominated with Food Lovers topics, rather than seeing the Shoutbox in that list.