It is my understanding that you can carry in restaurants however bars and liquor stores are prohibited. The easy way to check for that is see is there is a sign at the door that you must be 21 to enter. If there is a sign then chances are it is a prohibited area. If it is a restaurant that also serves people under 21 then you are ok. Btw carrying at parades that require a permit are also prohibited in La. I take that to mean mardis gras parades in New Orleans.
Have fun and stay safe.