The Meaning of Beggars

If a person goes begging, then they ask. They go out and try to find money or food or charity. But if something goes begging, it means that it's free to be taken by anybody who wants it. So for example, there was a party in the office, a different department,. And they had a load of food left over. And well, that food went begging, didn't they? It certainly did. We came downstairs and made me asking, are those sandwiches going begging? And they were like, yeah, help yourselves.