This was an April Fools joke (and presumably a dig at obesity in Samoa) that refuses to die. <a href="https://en.wikipedia.org/wiki/Samoa_Air" rel="nofollow">https://en.wikipedia.org/wiki/Samoa_Air</a> ceased operations in 2003.
As much as I hate sitting next to a whale who is trying to occupy half of my seat, according to <a href="http://en.wikipedia.org/wiki/Boeing_737" rel="nofollow">http://en.wikipedia.org/wiki/Boeing_737</a> a fairly typical jet while empty is about 62,000 pounds, and can carry a maximum of 124 people (in most configurations less). That's 500 pounds of plane per seat.<p>For the vast majority of people, your share of the empty weight of the plane exceeds the weight of you and your luggage by a good margin.