They are adults, they know how hungry they are. They know what types of food they like. They can order an acceptable amount of food for themselves.
Stop eating off others plates because you think its cute. It isn’t. It’s annoying.
Edit: If I am out to a restaurant to eat with you and you didn’t order enough food for yourself, order more. We aren’t being given rations and I don’t care if you eat a large amount of food.
So how is the expensive, needs specific maintenance at regularly scheduled intervals with specialised tools, and parts you can only get from one manufacturer financial freedom?