Unfortunately for at least 24 people who have already lost homes, the answer to this question, Is there such a thing as volcano insurance in Hawaii? is no.
Living near a volcano is like living near the ocean. You "should" know the risks of living near natural hazards. But many measure risk by frequency of events and then take chances — given that "nothing happened here for the last 30 years that the people lived here before us" (a quote from my wonderful daughter-in-law, who I love deeply. They live 65 feet from an idyllic creek. What would it take for that creek to be a raging torrent? Rain maybe?
Anyway, you ignore hazards at your own risk. Many get away with it for years and years. Then, some have to pay the piper.