Can you explain the significance of making an offering to a Guru, based on the story of Kaka's grapes?

The act of making an offering is a significant expression of devotion and respect. Chapter 35 highlights this tradition, stating, "It is not good to go empty-handed to the door of God, a priest, or a Guru." In the narrative, Kaka buys two seers of grapes to offer to Sai Baba. This offering, though seemingly simple, becomes the very instrument through which Baba teaches a profound lesson to another devotee, Boss Dharamsee. The grapes, initially with seeds and disliked by Dharamsee, are miraculously transformed by Baba. This shows that a devotee's humble offering can be used by the Guru in mysterious ways to bestow grace and deepen the faith of others.