Common sense and extra staff are part of history. The great British public decided (in concert with every other human being on the planet) that they wanted to get more flying for less cost. Your wife met the place where the cost and the service meet. That balance point can sometimes be changed by a member of staff exceeding their authority. But, if they did it for this case, they have to do it for every case and that is not what LCCs do. What happens to staff that consistently exceed their authority? They lose promotion and, possibly, their job.
With apologies, that's one of the most eloquent and accurate explanations that I've ever come across - Gold Star and a choccy biccie for the PAXboy!!!