FULL DISCLOSURE: I have some class issues.
As some writers have already noted, a big part of the draw of Fifty Shades of Grey is not the kink or sex, it's the bling. If you extract the narrative (not difficult) and the dialog (if only we could), the Fifty Shades movie is basically a video catalog for some of the posh things that enough cash can get you. (I mean, in addition to enhanced tracking capabilities and support staff who won't even blink at your order to tow and sell the car of the girl you're stalking.)
In both the movie and the book, the protagonist Ana—the blank-slate character against whom viewers/readers can easily project themselves—comes from a humbler background, not poor, just, you know, humbler. An everyday person. Her life B.C. (Before Christian) is in bright colors and jumbled chaos. It's your standard college bohemia, well, faux-hemia, because it's the movies and any realer will take you out of rom-com territory. But you know, Ana has to work at a hardware store. Wow. Much humble, so relate.
Christian, on the other hand, has the money. He has all the money, and he lavishes it on his monochrome, pristine cars and watches and wardrobe and apartment, and on his equally monochrome and oddly sterile Red Room (OF PAAAAAIN). Christian gushes wealth all over Ana, like, drips it on her in scene after scene of symbolic "money shots". If not the strongest factor for Fifty Shades' popularity, the millionaire porn aspect is definitely in the top three, because poor girl/rich man has been a solid weapon in the romance-writing arsenal since before Pride and Prejudice.
At the same time, everyday people don't really trust posh nobs, so showing Christian's money is a handy shortcut for putting him in the "Do Not Trust" category. Not that there are not many other red flags a-flying in this film—SO MANY RED FLAGS—but Christian's wealth and willingness to use it in pursuit of his "specialized interest" absolutely nail the stereotype to the highly polished mahogany table: very wealthy people are self-interested and amoral.
My knee-jerk socialist lizard brain says, "Well, duh," and we could certainly discuss how massive quantities of money that one didn't earn oneself could have a corrupting influence in one's life, but again we'd come back to the problematic equation that kink = corruption and WHY is this movie promoting that again? Anyway, I'm more interested in other questions, like how Christian's kink isn't really challenging a goddamn thing. It's set dressing. Very little of that expensive shit hanging on the walls gets used, and anyway, Ana doesn't want it.
Unlike Christian, who supposedly needs his elite brand of BDSM to be satisfied, Ana doesn't need the expensive items. She's just folks, remember? She doesn't need leather restraints and a set of antique Japanese canes (well, that's how they're racked up in the film, fucking orientalist bullshit) and an elaborate drop-down support structure for standing/hanging bondage. She doesn't need any of that. She just wants to touch Christian without asking permission. And go out to a movie. And get sensually eaten out on a regular basis. You know, the "normal relationship" things. None of that posh pervy stuff, with all the gear.
The thing is, no one NEEDS all that gear. Sure, if you have the resources and find it fun, you prioritize it as part of the budget, but consumption of kink goods is higher up on Maslow's Hierarchy of Needs. It just is. You can frequent Home Depot and the dollar store, NOT to stalk the love object of your dreams and aggressively buy suggestive items at them, but to actually stock up on playthings on the cheap because that's what poor pervs have to do. We repurpose wooden rulers and thrift-store belts and clothes pegs, because that's what you do.
But that approach doesn't sell product, and that is part of what Fifty Shades of Grey needs to do. It is an aspirational film, heavily tied to the look, the accoutrements of kink. The audience has plenty to strive for; here is kink as a sign of class. Not too much. Not too hard.
That's the great thing about a video catalog: you don't need to dig deep in order to shop around.
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