may i suggest that, historically, 'the rich' in britain were going to end up literally running the country, and so the expunging of all that youthful 'spunk' and 'high jinks' was seen as an allowable extravagance in lives that would end up rigidly (if comfortably) orchestrated around making damn sure the money and power stayed in the right pockets (traditionally known as 'public service').
'the poor' were never going to be in charge of anything, and so didn't deserve or require the same leeway when it came to pig-fucking. no steam to let off, so to speak.
now, of course, we are supposed to live in an opportunity society, in which, theoretically, anyone might end up in a position of power and/or wealth.
so, theoretically, we all ought to be afforded the same liberties during adolescence.
that is clearly not the case, as we seem to be being pulled toward a 'neo-feudal' society in britain at least.