What is the significance of Bakha asking Ram Charan to toss him a sugar plum instead of taking it himself?

When Ram Charan holds out the sugar plums in his handkerchief, Bakha refuses to violate the caste expectation that he not take something from Ram Charan's hand. Instead, he asks Ram to toss him the sweet. This is confusing for his friends, because they do not follow such rules among themselves--and so they know that something must really be bothering Bakha.