In defense of Hawaiian pizza, or at least pineapple on pizza, I think I should mention Spiros' Anna's Island pizza, which is chicken, pineapple and spicy tomato sauce... It's excellent and the depth of flavour added by having the spicy sauce is just what the traditional Hawaiian is missing.
That said, my kids find it too spicy so they don't eat it and, if pressed, there are other pizzas that I'd rather order, so we rarely get it... But it's still really good when we do