How does utilitarianism promote a more efficient economy? It seems to me that implementing utilitarian ethics would create such an omnipresent bureaucratic apparatus that everything would crawl to a halt.
I've seen utliliarianism in this thread, defined as something that has "happiness" as its goal. If that were the case, it should be called "Happitarianism", but it's not. The core of utility is functionality, and obtaining the most functionality, so that your economy works better, so that people probably can be happy, if indeed they view consumerism and prosperity as happiness. (Which there are some doubts) But, the prime objective is for your kingdom to work, because if it doesn't, you are dead. In a blunt way, evolution shapes the rules of utility, so you have no choice but to adopt it as a basis.
Typically, people understand morality as a form of utilitarianism, because they can always argue for the rules, in terms of whether it will hurt their country. Should we pay welfare to single mothers? Well, no; because blah blah blah, blah blah blah, blah blah blah, blah blah blah, blah blah blah, America will fall, and be invaded by Islam and Mexicans.
Utilitarianism has problems deciding some issues, like abortion and euthanasia. Say, I make a rule, which says that all babies with birth defects should be killed. We should logically do this. In BC days, people used to leave their kids out in the snow, to check how hardy they were. You will notice that there is no mention of what to do with a defective baby in the Bible. Important issue, right? Glossed over. The problem is: what type of people does it make us, if we can
kill our children? This might wash in Klingon society, but would the Klingon economy really work, and out-compete others. I don't know.