Originally Posted by Avman
Do I spot a security flaw here then?
No.
BA, BMI and other domestic operators do not have the "show photo-ID" requirements of the low cost carriers. I have never been asked for this on their domestic flights. This is a revenue protection matter, NOT security related, to overcome businesses buying lots of cheap tickets on the low-costs a month beforehand then sending whoever they want on the day.
Of course if it was described like that it would be open to challenge so it's all dressed up as security.