There's more than just bigotry at play here. We're constantly told now, "If you see something, say something" (the article even pokes a little at this), then our fear factor is raised as high as possible with notions that any of our fellow passengers could be evil terrorists about to bomb the plane. To top it all off, air travel is stressful and if you have even a little bit of fear of flying it gets amplified by the whole experience. It's like the perfect cocktail for these sorts of situations. I'm always surprised this doesn't happen more often.