Witzend
There are always OTT attention-seeking celebs at such do’s, hoping to be photographed and plastered all over the papers/social media.
As for ‘Kleider machen Leute’ I prefer our ‘Manners makyth man’ though I can’t remember who said it.
"Manners Maketh Man" is primarily attributed to William of Wykeham (1324–1404), a 14th-century Bishop of Winchester and Chancellor of England. He famously adopted it as the motto for his educational foundations, New College, Oxford, and also Winchester College.
So possibly Colin Firths character in Kingsman was a Wykehamist? (Alumnus of Winchester)