In a food truck I can usually see the person cooking the food as well as the person giving it to me.

I will also eat the food close to the truck, meaning it's very little effort for me to go back and say "oi, this is shit, mate".

In a ghost kitchen you have zero way to actually give feedback to the kitchen itself.

A ghost kitchen is like an LLM or an ephemeral container, or any stateless instance. Even if you could impart some feedback, it would be gone by the next time you place an order.