Originally Posted by
Nicofr68
And as a matter of interest why do they care if we don’t do the last leg on a cheap ticket surely they save the fuel of an absent passenger’s weight?!
Because you have not paid the higher fare for the travel which you always intended to take. The difference may well be more than the fuel saving that you mention.
Whether any of that is enforceable, in practical or legal terms, is always the subject of hot debate here. But there can be no doubt as to why BA cares about this.