I'm not a vegetarian, but I know better than to eat most airline food even in F. We brought our own food for our flight from OGG on Sunday - sandwiches we picked up at the Lahaina Farms Market. Most airports that AS serves in Hawaii will have some sort of vegetarian option - veggie sushi, pizza, some sort of sandwich that will hold up for a few hours.
If not, I would highly recommend one of the picnic packs from coach.