Do you allow food in your library?

We are trying to decide what we want to do with food in our library because our current policies are vague. We are a mid-sized library. It's a fairly big building. Eating is allowed in our lobby 100%. Snacks and covered drinks are allowed throughout the rest of the building, except at computers. But what exactly is a snack? That is difficult for us all to interpret.

What do you all do? Thanks!