Actually, the cost of alcohol in Hawaii is reasonable. Even if there is a difference, it's not that much to make it worth having you lug it over on the plane. It is even cheaper when you buy it at Costco here.
My friend's brother works at Morton's in the D.C. area and was married here. He found that his favorite wines and champagne were cheaper here than at home! He bought bottles to bring home with him.
TF
