Why are some specific causes of why there are shanties surrounding the hillsides of Venezuela, Caracas?

they are the so-called "informal settlers" who cannot afford to live in legal residences because of higher rents and maintennance so they built shanties and put up illegal wiretaps connections for their electricity and water....as rich as venenzuela is with its oil revenue there are millions who are really, really poor and have to resort to this kind of living....and its not only in caracas, venenzuela..it is all over the world...very, very sad..indeed!!!!