On Kauai it is totally legal to bring your own bottle of wine into a restaurant. Most restaurant corkage fees, the price charged to bring your own bottle, is between $20-$30.
I have not had any issues or attitude with bringing my own bottle into any of the places on the North Shore. Some places have better glassware than others but that would be my only complaint. When I bring a nice bottle of Burgundy, I sometimes bring my own glassware. I have become a little eccentric I suppose.
If an establishment does not have a liquor license, then they usually do not charge any fee to BYOB. It is important to know that we have open container laws in Hawaii so if you are traveling with an open bottle of wine it must be stored in the trunk and completely out of reach.
All restaurants that we know of allow corkage on Kauai.
If anyone has any experience about corkage on Kauai please be feel to share with us.