Eww. Was anyone sitting next to the guy? Is this the TSA's fault for allowing a loaded weapon aboard? I wonder if we would all be less grossed out if a woman had being using a vibrator or something. I for one would be okay with that. Of course that's not as messy. If it had been a woman do you think someone would have hit her with a book?
I agree that vomiting is even more disgusting and likely to lead to a chain reaction but vomiting is involuntary. So you can't really make it illegal. I don't mean to belabor the obvious but that guy was clearly insane. That's practically the definition of crazy. Disinhibition, no sense of reality etc. Now I'm going to be all paranoid if my seating area smells faintly of bleach.