I am merely speculating here, but this may have originated in the US. After all, all the US majors charge various baggage fees. It started with domestic flights, but why not expand that money maker to int'l flights, right? It is a bit weird to charge pax originating in the US and not the European counter parts. I mean, if there's money to be made and customers to be screwed... why not? I suppose it was only a matter of time before EU airlines followed suit.

My only problem with this is the fact that it's just inconsistent. Back in the day you paid for a ticket and everything was included (food, booze, luggage, etc.) Nowadays there's a clear tendency to itemize. Pax only pay for what they get, with food, drinks, IFE (for domestic flights in the US) being extra. Bug charging for extra weight in the form of baggage fees is shortsighted. What about what people weigh? (I am assuming the argument here is more weight means more fuel being used.) I have flown with many pax who were over 23kg heavier than me. Shouldn't I be allowed another free bag for that reason alone? Unless people are weighed, too (I'm not advocating that!)... this fee is just illogical.