I think it just means the witch came for food or money every day. Likely leftover food from the inn.
beg [VERB]
1.1 [WITH OBJECT] Acquire (food or money) from someone by begging:
"a piece of bread which I begged from a farmer" (ODO)
EDIT: Regarding the quirky preposition, it is likely either a personification of the business inn rather than the building (Thank you AndyT).
Of course the witch doesn't beg from the building, but from a person working there. But to avoid defining that she always begs from the cook or the inn keeper - which isn't important for her as long as someone from the business inn gives her food.
As Peter Shor points out in the comments, it is possibly a translated text, so the preposition could stem from a wobbly translation from Italian as well.
