It's a concept that we've seen coming for a while - an airline that requires you to pay for your ticket based on precisely the capacity of weight that you take aboard. What that means is that not only do passengers pay based on their own physical weight, they pay by the weight of their luggage as well.
The airline that has implemented this business structure first is Samoa Airlines, at it comes as no surprise that this idea is being discussed controversially. There is, of course, that whole issue of weight-based discrimination. However, the concept does have sound business sense, as naturally a heavier load aboard a flight comes with a greater financial toll (and is more taxing upon the environment as a result of required fuel use). While other airlines have begun to charge larger passengers who require more seat space on the plane, and others still have changed they way they approach charging for heavier baggage, this is the first airlie to go about both these things at the same time.
And, whether you like the idea or not, we probably shouldn't be betting that it will be the last airline to use weight to determine ticket prices.