My inestimable thanks to the commenter who linked to this exquisitely germane wiki in the comments section of my post below:

Sumptuary laws (from Latin sumptuariae leges) were laws that regulated and reinforced social hierarchies and morals through restrictions on clothing, food, and luxury expenditures. They were an easy way to identify social rank and privilege, and were usually used for social discrimination. This frequently meant preventing commoners from imitating the appearance of aristocrats, and sometimes also to stigmatize disfavored groups. In the Late Middle Ages sumptuary laws were instated as a way for the nobility to cap the conspicuous consumption of the up-and-coming bourgeoisie of medieval cities.

I was wrong about Cameron. He is not trying to drag us back into the 19th Century, he is making a bid for the 14th Century!! I suppose it may be to some advantage that we know exactly what is driving him and his ilk. Of even more advantage is to accept that the struggle for freedom, prosperity and progress is necessarily going to encompass some degree of class war.