Well, adding my two zuzim (Pesach is coming!): I always thought that "beruf" meant "call" rather than "calling". Each peddler had his or her own call to tell people what was for sale. This little boy (or the precious white goat who symbolizes him) would be so special that instead of selling rags or pots or onions he would sell sweet and delicious raisins and almonds.

Aloha,
Mark