Alright, I'll throw my hat in the ring. I think REALSMOOTHIE gave a pretty good outline of marriage from a pragmatic, historical basis. I'd only add that I think this 'arranged alliances' purpose of marriage lasted up until the Victorian age, not the 1940s-60s. If you read the Art of Seduction by Robert Greene and pay attention to the introduction in particular, there's a very good outline of the covert, psychological and sociological aspects of how women have historically manipulated exactly the marriage conditions REALSMOOTHIE described in very calculated ways. Essentially, seduction became a very sophisticated art as a response to exactly the powerlessness women found themselves in. So while I'd agree that seeing marriage as some grand scheme for women to control men, I think it's equally misguided to believe that women are above subterfuge and psychological manipulations. In fact I think the best social convention women have ever established was to condition men to believe they're random, fickle, indecisive creatures given to the whims of emotions beyond their control. The combination of the female prerogative (she can always change her mind) and the Feminine Mystique (women are always unknowable) has been their tools of the trade for centuries. Make no mistake, women are VERY calculating, and consistently more so than men in general. They've had to be.
But that's marriage, not romance per se. There will always be an element of fantasy and idealism that can never be realized, but always be sought after. Women (and really any gender) will always be happier in that discontent, because it makes the times that it's gratified all the sweeter. The idea of Romance just happens to be women's food of choice. In fact it's very similar to shopping; it's not the buying that gets them off, it's the act of shopping, it's prolonging that purchase to better savor the experience. It's foreplay. Forestalling the climax to heighten the experience.
When I was 26 I had a workout partner named Dean. Dean was drop dead gorgeous, unbelievably cut and women would flock to the guy regularly. Dean was also a male stripper at one of the strip clubs that had a male revue night once a month. The guy made money hand over fist and was always a crowd favorite. I was dating a stripper named Angie at the time so I was pretty familiar with the club owners. One thing I noticed about the most successful male strippers was that they were almost universally the ones who sold a story to the women in the audience as part of their act. Dean used to do a Fireman skit that would drive these women (young and old) into a frenzy. Another guy would do the hot executive fantasy in an Armani suit and give away flowers to the ladies, classy, but building up to him stripping down to a thong. The guys without an act never made as much in tips. It wasn't as satisfying for the women as the fantasy aspect that Dean and a few others would sell. Women get off differently than men. For a guy, a hot stripper in nothing but a g-string grinding out a lap dance is enough to get him aroused. Women need that ungratified fantasy to get them aroused.
It's the anticipation. I could go into detail about how all the most traditionally romantic behaviors women associate with romance originated in courtly love contests with suitors trying to out do others with poetry, sonnets, acts of devotion, etc. but these are the behaviors, not the motives that prompt them. Women need a build up. Yes, romance has an unbelievable potential for manipulation, but it's that nagging, itching, sexual anxiety that, as much as they'd like to protest the opposite, is what they enjoy the most. Uneducated men simply don't make this romance-to-anxiety connection and the prospect of being romantic gets distorted and borken down into simple acts - "if I bring her flowers, she'll be inclined to ƒuck." This is the AFC who thinks comfort and familiarity are the path to intimacy - wrong!
On several threads I've made a point of guys encouraging and propagating a woman's anxiety. Whether that comes by way of perceived sexual competition, uncertainty of sexual satisfaction, teasing, flirting, neg hits or positioning her into qualifying for him, the point being a sustaining of the discomfort of that anxiety. It's the discomfort that heightens her arousal, peaks her interest and makes her pursue.
Far too often this is a principle that's entirely lost on damn near EVERY AFC. AFCs think that perpetuating anxiety is counterintuitive because they believe in the filtering social convention that women want comfort, rapport and familiarity in order to become sexual. They swallow the "friends-first" mythology and so, deductively, they spill out their life's story as fast as possible in an effort to make her as comfortable as possible (and get sexual as fast as possible). The AFC isn't perceived as Romantic for exactly this reason. There's no fantasy entertained, no anticipation and his attention is worthless because she doesn't have to earn it. He gets frustrated because he's doing all the Romantic 'things' but she still isn't sexual, and most likely sees him as a friend, all because he's gone wholly over into the comfort and rapport stage by preempting the anxious, sweaty, nervous, uncertain arousal stage that she love every moment of, but will never admit to enjoying.
It's discomfort, not comfort, that makes for memorable romance. How often do you hear women complain of how the romance faded after marriage, while the man complains about how the sex drops off? The anxiety that made marathon sex so great, bourn from an urgency of anxiety, is replaced with comfort, certainty, familiarity, routine, etc. That's not to devalue those qualities in a relationship, but it is to highlight the vital necessity of maintaining a woman's anxiety levels within an LTR. What she seeks in Romance after an LTR or marriage is established, is a return to that heightened, anxious state of arousal that made her wet in anticipation for her Man. That's the heart of romance that guys need to cultivate with their wives and LTRs.