Thomson ReutersThe push for chorizo to be the protein savior for Chipotle Mexican Grill has come to shove. The burrito roller confirmed to CNBC on Monday that it's getting rid of the savory pork-and-chicken sausage. Quick-service eateries shake up their menus all of the time. Taco Bell fans don't expect the Waffle Taco, the Enchirito, or the new Naked Egg Taco to last forever.