It is important for a local government to have all its residents registered on the Padron as they are allocated regional and national budgets, based on the number of residents in a town. It can be the difference between having a fire station, road investment and community swimming pool.
You will be asked to produce a Padron for many administrative tasks and purchases. Basically, it is a proof of address. You will need one to buy a car, change your driving licence, register for health care etc.
It is relatively easy to obtain a Padron in the office of the council in the Old Town of Javea. There is an English speaking helpdesk, although you only need a few words and the relevant paper work- which are your NIE or Residencia, passport, a rental contract or your property deeds.