>>28215572In fact, all searches for the legality of sand castles in Hawaii lead to /vp/ threads about sand castles being illegal in Hawai'i.
I live in Hawai'i. It's illegal to have two drinks in front of you at once, to store coins in your ears, and to not own a boat. It's illegal in my country to own a gas-powered leaf blower. Twenty-one is the minimum age to purchase tobacco. But sand castles are certainly not banned.