Why do you guess this? Have you tried it? Normally when you refuse to pay a stated amount, the rate goes down, not up. Showing a zero rupee note indicates that you are not bargaining, you are taking a stand against bribery. We have used the zero rupee note to refuse to pay bribes on the train, with the result that we pay the full fare and demand a receipt. What the ticket collector is trying to do is cut a deal where we pay less and get no receipt - so he can pocket the entire amount as a bribe.