My personal opinion about this is not made up yet, it's tough.
But a thought that occured to me after reading a a thread in Free your mind about American Freedom is that alot of people in there meant that for example health care wasn't a right because that means that someone else has to help pay for those who can't pay for themselves, via taxes and that was to increase someones personal freedom.
If you transfer that thought to this. If big people won't have to pay for two seats if they need it it means that the airline has to get the money for that lost seat from somewhere else, most likely on the price on the rest of the tickets which is pretty much the same as charge more tax from everyone to be able to give everyone health care.
So is it a right to take a flight?
I don't say that this is my opinion, just something that I came to think of after what was said in that thread and that can be compared to this. Specially since alot of people say that you not always can help being big, which I agree on, partly. Just like you can't help if you get sick. Should you be given "help" in both cases, none or in one of them, if so which one and for what reasons?
I have no idea if anyone who has answered here also participated in that thread, if so, what your opinion were, so I'm not picking on anyone, just thinking.