I am constantly saddened by Kimmel's daily question. He will get a reporter to ask a completely nonsensical question to passersby on the street, and they seriously attempt to answer it. It is hilarious, but oh so sad. I can only hope that the whole thing is a setup, and that those poor twits are actors.
As to the whole gluten thing, you can't be gluten free if you don't know what it is. You have to read every label, because wheat and other gluten-containing grain derivatives are in everything, or at least possibly cross contaminating food. I did a gluten elimination trial a while back, and it was nearly impossible. I feel sorry for people with Celiac disease (although I am not totally sure I don't have some wheat problems, too). The people who claim they are gluten free on this clip are imposters. And that last guy eliminated everything fun right out of his diet! Poor b@stard...