Are you equally pedantic on the colloquial classification of nuts when a large portion of the "nuts" we eat are actually drupes? Or fruit vs vegetable classifications? Perhaps language is a tool used to convey meanings and ideas in ways that are quickly and concisely understandable. The "plant-based" insert_animal_food_name allows people to understand that this food item is meant to mimic an animal-based food item, except it's derived from plants.