Why did the shopkeepers in Shirdi decide to stop giving oil to Sai Baba?

The narrative in Chapter 5 explains that Sai Baba would bring a tin pot to the shops of grocers and oil-merchants every day to beg for oil to light lamps in the temple and mosque. While this continued for some time, the grocers eventually grew tired of the practice. The text states they got a "wicked idea" in their minds and conspired together, deciding that this "nuisance must stop now." It was this collective decision to no longer provide free oil that led them to unanimously refuse Baba when he came on his daily routine.