Smoothies often require you to freeze ingredients. Some desserts may require you to freeze the final product before you can eat it. Homemade ice cream, depending on the recipe, will require you to freeze it. Generally, most recipes don’t require you to freeze ingredients or the final product. If anything, most recipes ask you to add heat or chill - not freeze. The difference between chilling and freezing is where you put the item.
You chill in the fridge, but freeze in, well, the freezer. It is honestly as simple as that. If a recipe requires you to freeze it, the recipe usually states so. This is to help every cook make the recipe right, regardless of how much experience they have in cooking.