Translation is always tricky, but I remember this slightly different:
Figs were an imported delicacy at the time, and the donkey just managed to eat them (without being given any on purpose). Seeing a donkey eating several times their own value in figs, the philosopher looked to his servant who might have been standing there either in shock, despair, or both, and said something along the lines of “Oh don’t just stand there. Get him some (undiluted) wine to wash the figs down with”. With (undiluted) wine also being an expensive drink.
I feel like that context makes it funnier. Basically like standing in front of your burning mansion with a butler, meeting their eyes, and telling them that you still feel a little chilly and ask them if they could put on an extra log or two.
