The Satcharitra mentions a puzzling incident with two men from Goa. Why did Sai Baba accept Dakshina from one but reject it from the other?

Chapter 36 describes an incident where two gentlemen from Goa came for darshan. Sai Baba asked for and received fifteen rupees from one, but when the other tried to give thirty-five rupees, Baba refused it. The text highlights that this caused great surprise among the onlookers, prompting Madhavrao to question Sai about this seeming partiality. While the source text from this chapter narrates the puzzling event and Shama's subsequent question, it does not provide Sai Baba's reason for this specific action, leaving the reader to anticipate the explanation.