Why are non Italians,people of non Italian ancestry being portrayed as "Italians" in Jersey Shore?

I have no respect for any of those people(foul mouth,vulgur language,sleazy clothed females(they may be pretty and attractive,but they lack a brain!).Those people do NOT reflect true White Italian Americans or Italians in general.This show simply only reinforces the negative stereotypes that already exists in the United States towards Italians and Americans who are of Italian ancestry.