Historically California had some of the strongest anti-Asian sentiment in the country, already in full swing by the late 1800s, and also one of the larger Asian populations, so it's not surprising that they had the greatest number of internment camps. While California had long been developing laws to remove as much of the East Asian population as they could, and later getting these laws made national, Hawai'i always had a much more lenient view. Hawai'i wasn't a state until 1959, and what laws were passed to exclude/limit/reduce East Asians that did go into effect in Hawai'i came later than on the mainland.

That's not to say there wasn't anti-Japanese sentiment in Hawai'i as well — see e.g. Okihiro, Gary Y (1991) Cane Fires: The Anti-Japanese Movement in Hawaii, 1865–1945 — but it was certainly less pronounced compared to places like California, which as soon as the Chinese had been explicitly restricted, immediately then turned its attention on the Japanese residents.

Additionally, in Hawai'i the population of Japanese Hawai'ians was massive. It was a huge part of the total population of Hawai'i and it would have been incredibly disruptive to detain them all. This caused a number of non-Japanese Hawai'ians to resist internment as well since otherwise it would have killed the economy to see them all taken to the mainland. Hawai'i had also instituted martial law, which helped calm people's fears about the potential rist.

Put simply, Hawai'i just didn't have the same climate of anti-Asian racism that was then thriving in in Mainland America.