Chief CrunchyCon Rod Dreher likes occasionally to mull over things and make "discoveries" which are utterly obvious to anyone who has thought about social conservatism for more than the last hour or so. He asks whether his readers have ever wondered why the poor and working classes tend to adopt the more conservative forms of religion. Why yes, I wondered about that back when I was an undergraduate and so no doubt has everyone else who has ever had conservative instincts and the slightest interest in political theory or philosophy. I suspect that this manner of approaching this stuff fulfils a didactic function for Rod; for some reason he has and has retained a large number of liberal commenters who have never thought seriously about these things and is trying to break them in gently. Sure enuf there were a few commenters who seemed to be transmogrified by this brilliantly original line of thought.
Rod buries the lede further by launching into a digression about the superior personal appeal of charismatic varieties of religion over liturgical ones to the most poor and oppressed. He finally gets to the answer to the question: the poor and marginalized are drawn to religions with rules and moral structures because they have the most to lose through moral dissoluteness. If you descend into the depths through drugs, promiscuity and self-indulgence, and you are wealthy, dad and mom are always around to subsidize you in university for a few extra years until you can get your head together and straightened out. The poor have no such cushion. If you as a young man get in hock to bookies you can always get dad to bail you out at least one more time before the legbreakers pay you a visit. If you're struggling when starting out in the workplace, dad has contacts; later on if life just hasn't gone the right way you can at least look forward to inheriting the family's property when they pass on to give you one more chance or spree, however you decide. The wealthy and powerful have a larger margin of error.
There are other reasons as well, looking at the question from the obverse side. Why do the wealthy tend towards the liberal forms of religion? Well, what's distinctive about conservative religion? It counsels and demands self-restraint, restraint on one's use of power. Who has the most power to be restrained? The wealthy. Therefore they have the most to give up by adherence to conservative religion, and can be more easily assuaged by liberal religion which puts its restraints on others, demanding they refrain from cutting down trees or contributing to global warming.
Rod cites James Poulos over at the American Scene who, discussing the appeal of the odd new sect known as liberaltarians, refers to the Sex Vote, that segment of "people who are generally willing or even eager to trade away political and economic freedoms for broad (in terms of scope, variety, protection and enforcement) social and cultural freedoms". I think Poulos misunderstands what these people want, though. The cultural and sexual freedoms these people want they already have, and have had without threat for decades now. What they want now is to achieve cultural hegemony for the libertine approach to life and marginalize those who oppose it, through their control of mass media and elite institutions plus the occasional unbaring of the heavy hand through boycotts, firings, and the ministrations of the Human Rights Commission.