Politicians don't have the power to stop people from doing dumbass things. Or, at least, not for long.
During the Italian Renaissance, there was a massive gap between the haves and the have-nots. There was also a culture of massive conspicuous (over)consumption, in which the artisan and small merchant class would try to "fit in" with other upwardly-mobile people. This meant they would grossly overspend on entertainments, clothing, food, and especially dowries. Everyone wanted to prove that he or she had as much money as Lorenzon de'Medici, but too many people were getting in debt as a result.
So, in order to maintain the status quo and rein in some of the spending, Church and secular leaders in Florence and some of the other Italian city-states developed "sumptary laws" which attempted to curb people's spending. All of a sudden, there were limits as to how many dishes you could serve at a banquet, how much of a dowry it was legal to give, how many servants you could have, and what kind of clothing you could wear in public.
In the short term, the servants and merchants who made a living catering to the big spenders (but who did not belong to a class where they felt obligated to participate in the overconsumption) were screwed financially because their livelihoods collapsed. A few wealthy people and social strivers were moderately embarrassed when they got caught violating the laws, until it occurred to them to start competing with each other to find ways to get around the sumptary laws. The poor didn't get any richer, nobody was induced to save instead of spending, and politically it accomplished bugger-all except to get large numbers of people pissed off at the Church and at their governments.
