A number of Polynesian groups most certainly were, and there is an oral tradition or folklore of it in Hawaii.
“....oral tradition or folklore of it in Hawaii.”
And we all know how accurate oral tradition and folklore is. Take, for instance, the menehune, or Pele, or my own personal Amakua, Lono.
Half of my family are from Polynesia and the islands. I was born and raised not only in Hawaii, but in the culture as well. I have yet to hear about cannibalism being a intricate part of Hawaiian society.
I will contact my family on the Big Island. Tomorrow to find out if they can provide me with any insight. They would know more than I.