IMO, Bollywood celebs become powerful either by showing support openly to a governing political party or by making huge donations to parties, so if anyone is powerful in Bollywood it is because they did one of the above mentioned things.
Also, grudge on not donating the expected money is real. There is one incident happened in my hometown. When my father, who is a elected member of one of the NGO along with his colleagues approached one of the leading glass businessman and requested donation, the businessman was like you can quote any amount, I will donate it without arguing. The answer surprised my father and when he asked the reason, the businessman explained one of his recent experience. Apparently few party members approached them with the expectation of huge donations and when they didn't get the expected amount, they didn't allow materials to be unloaded with the help of labourers. Later the businessman unloaded it with the help of inexperienced people which resulted in breaking the glass materials.
Also when one of my aunt gave 2000 Rs instead of 10000 rupees on ganesh utsav related activities. They threatened her to interrupt the ongoing house construction but luckily for her, the governing(state) party union members supported her.