We have big hawaiian culture resort in Japan, they can enjoy hawaiian culuture there even if they can't afford to go to Hawaii. I used to go that resort often when I was little with my family, so I liked hawaiian culture since I was kid.
Historycally, Japan has relationship with Hawaii for long time. Around 1900, a lot of Japanese moved to Hawaii as migrant workers. They both from island and have same way of thinking. Japanese and Hawaiian both believe every one of existence like woods, rivers, oceans has a God's spirit. We have same spirit which is harmony with nature.I guess they feel similarity and comfortable about Hawaiian culture.
Addtionally, The dance style is very similar with Japanese one. Hula dance need to bend knees a little bit, keep the center of the body low and tell the story by using hand motion. That is very similar to Japanese traditional dance.