Why did Cholkar stop eating sugar, and how did Sai Baba later show him that he knew about this personal sacrifice?

After making his vow to distribute sugar candy, Cholkar passed his exam but faced financial difficulties that delayed his trip to Shirdi. As described in Chapter 15, he felt he couldn't go empty-handed and had to keep postponing the journey. As a personal penance during this delay, Cholkar gave up sugar, considering it an 'inedible substance' and even drinking his tea without it. When he finally reached Shirdi and fulfilled his vow, Sai Baba demonstrated his omniscience. As Cholkar was leaving with his host, Jog, Baba specifically instructed Jog to 'Give him cups of tea, well-filled with sugar.' This specific instruction amazed Cholkar, as it proved Baba was aware of his secret, personal sacrifice.