The crumbs and residue from snacks will attract rodents and other pests. These pests will then look for other things to eat, like the glue in book bindings.
Apply common sense: clean up after yourself or you may be asked to leave.
In OSF:
You may eat small snacks in the library and drinks are allowed in covered containers (no glass).
Dispose of wrappers and cups properly.
If you are in the mood for eating larger amounts (meals for example), please do so in the area near the tunnel entrance to the library, but not in the library itself.
No "food deliveries" to the library for individual patrons or small groups of students. Library-sponsored events and meetings often involve catered items.
In Keffer:
Light snacks and covered drinks are welcome in the Keffer library; larger meals should be eaten outside the library.
In Ireland:
No food or drink is allowed in the main areas of the library, the reference room, stacks, carrels, etc.
As you enter the library, there is a lounge to the left where food and drink is allowed and there is a refrigerator for short-term storage.