The film depicts the consequences than can happen if a person goes terribly hungry.  The human psyche becomes unbalanced  and people become irrational. There is something disturbing in  the situation and while not directly mentioned, it was implied that the people in that house  consumed  the old man's lower extremities.  Just as someone came in with a sackful  of potatoes,  all is not well  still, as it seems the man is mentally unstable.