When I was a collegian, we'd have potlucks in our chapter room (we didn't have a house) if it was someone's birthday or whatever special occasion. Sign-up sheets usually went out the week before so not everyone brough 7 layer bean dip.

Food was never consumed during the actual business meeting itself. Everything was eaten after. We never really had a no food policy during meetings, but everyone pretty much limited food consumption to small snacks or beverages.

Bringing food was purely optional and anything and everything was welcomed, even if there was no special occasion. The only thing we had to ensure was that the room was spic and span once we left.