I understand it was a very common thing many years ago ( 150 or more) for the wealthy to buy a "commission" into the British military for a useless son. In later times I am told it was still possible to buy a title, I can't confirm this but maybe others can.
Anyway, the story goes that in the early 1980's a particular Cathay chap and his wife bought a title and referred to themselves as Lord and Lady Bracknell or some such. The yarn continues that one particular day at Heathrow's Cathay staff counter the ground staff were calling names, loudly as they did then, and handing out boarding passes in dribs and drabs. After a while in a very posh accent they were calling for Lady Bracknell, "I'm Lady Bracknell, I'm Lady Bracknell" came the equally posh reply only to be told "you're off" in an East London accent.