If a restaurant ever tried to do that outside a licensed and inspected kitchen they would be closed down.
Agreed but that's not the point - to compare you have to look at the meal sharing concept, which is already causing restaurants headaches around the world:
https://www.mealsharing.com/
Why Home-Cooking From Total Strangers May Be the Future of Food - CityLab
BBC - Capital - Eat with strangers, make money?
FBW