If restaurants - from fast-casual to fine-dining - didn't pre-make/pre-prep some ingredients/items, your meal would take muuuuuuch longer to make. i.e. risotto, mashed veggies, some meats, vegs, pastas, sauces, salsas, etc., etc., etc. I could go on forever. Unless it's a raw food restaurant. Oh wait, no, they pre-make their stuff as well.