If you sell food to the public you need to be health department inspected in all States. Otherwise you are breaking the law. As well there are usually state taxes if take out food is taxed in your State and there may be vendors permits required from the town/city/etc.
You may find some exceptions for charity fund raisers to some of the items I mentioned but usually the HD requires something except here in FL and even then it's by county. At Naples they inspected vendors.
Retired competition cook. BBQ mentor.