To be fair to Keef, he sang at Westminster Abbey, but was never at Westminster (unlike McGowan). Strictly Dartford Technical College was Keef.
Mick, by contrast, was Dartford Grammar and the LSE.
Mick never pretended to be anything other than middle class, tbf. He was always the intellectual, cultured one. I mean, writing one of their best and most famous songs based on Bulgakov's novel and Baudelaire hardly marks him out as a man of the streets, does it?