The whole world revolves around money so if you are a person without money then you are as good as dead. Money is used to buy food, water and soon due to the pollution in the atmosphere, we will be buying air very soon.
Even if you don't have money you can still buy things that you wanted, you just have to convince people to buy you and give you things. For me the most powerfull thing in this world is not money, but the ability to control people.