How does the story of Amani illustrate the broader human tendency towards self-interest?

The narrative in Chapter 29 uses the innocent actions of the child Amani to reflect on a broader human trait. Amani's mind was solely focused on getting rupees from Baba; she would persistently say, "Baba, give me, give me!" with her attention fixed on the money. The text explicitly draws a parallel, stating, "The same longing exists in elders too - the running about is only for self-interest; only rare ones have the sentiment for the highest good." This idea is reinforced by the mention of the Madras people, who started devotional programs with an internal, "irresistible greed for money" after hearing of Baba's generosity.