When you look at the menu at a CS restaurant, the entree comes with everything that is listed in the description of that entree. If you don't care for a particular side that is included you can ask if they will switch it with a side that's included in the description of another entree. If there are separate sides with separate price points (usually listed farther down on the menu) those cannot be used as a substitution, but you can, however, usually purchase it with a snack credit.