I just find that if someone is making a film for sales, and sales only, there is no message to the film. Sure, some films are made for the sheer "oh that was neat." kind of factor, but at least in that instance the point of the film isn't just "haha, I got a quick buck." it's more along the lines of "here's a neat story, with some cool themes, and an something interesting to ponder."
I'd wish all movies could be more like "here's a neat story, with some cool themes, and an underlying message that will make you think about your life." but for the most part, movies today are like "look tits! explosions! fart jokes!"

Without having seen the movie and seen it in context, how do you know this is the case?

Because there's no point to showing a gratuitous sex scene without that being the case. You can quite clearly and quite easily create a sex scene without having to show "TEH TITTAYS!"
And because I myself have found this too difficult to put in words, I will quote a friend of mine from another forum
"I think that decades and decades of film making under stricter censorship laws have taught directors how to imply sex so that people who are adult enough to understand it will understand it, and those who aren't won't, and we really don't need to show a dude thrusting into a lady on screen. Not because it makes me personally uncomfortable (Although it does,) but rather because I think it makes a lot of people uncomfortable, and the people who derive joy from seeing that are either 1.) Undersexed porn fiends or 2.) Capable of deriving the same understanding of the character from a more subtle scene." -- Jeff

Sorry, but that just sounds like propaganda from a puritan agenda. Why not extrapolate that to violence as well? No need to show any kind of graphic violence since it can all be implied and anyone is capable of understanding the character through a less violent and more subtle scene.
Or how about special effects? No need of the eye candy, as much of that can be implied as well or done with simpler methods.
I'm not going to belabor the point, but when someone states they don't like something that's fine. But when they go on to say if you enjoy that thing then there's something wrong with you or that there's never a context in which it fits, then that's something else.
(Note: I personally don't care one way or the other if there's a sex scene in the movie. But I AM willing to give it the benefit of the doubt that it's contextually fitting until I see it. I may well change my mind once I do).

I do apply this to violence as well. And special effects. The less the monster is seen, the creepier it is, the more suspenseful. People say the same thing a billion times over on that one too, take for instance Silent Hill, where monsters hide under cars, and the most feared enemy wears a bigmask and you can't see his face.
Also, take into hand the saw series, and despite people going to see the excrutiating gore, there is still a large group of people who feel that it's a kind of porn film, or snuff if you would. Or those who boycotted the passion of the christ, it does apply to all areas.

Fair enough. I just personally think it's a silly (for want of a better word) reason to not see a film, especially if it looks to be a good movie experience otherwise. (If you're just not interested in the movie anyway, then that's cool).
In this particular case, I'd view it much as I do The Witcher game: the sex cards are juvenile and cheesy and pretty much just catering to the LCD (IMO). But as far as I'm concerned it doesn't detract from the game itself, which I found to be well worth playing more than once. Had I known about the sex cards before I bought the game, I doubt if that would have made me decide to not buy it. So it's the same with e The Watchmen. I very much enjoyed the graphic novel and I'm looking forward to seeing the movie. If the sex scene turns out to be lame and only gratuitous, but the movie is otherwise still good, then it won't detract from it for me.

I feel this has occurred with games as well... perhaps to a worse extent.
I think on the violence front, Hostel is a great example of a poorly made film, with very few redeeming factors, that got acclaim for having torture scenes in it.
On the sex front, or rather frontal nudity, I think it was probably worse in the past, where some films would have a tits out moment for no discernable reason. Some older horror films for example.
While I am of the opinion that its all acceptable (appropriate certification of course), the subtle touch is lost for most film makers in exchange for shock and awe. I think theres room in this world for both, surely?

I guess I'm sort of for the 'creator' point of view. If the author/director/artist wants to display nudity, fine. It's not my work. If I don't agree with it, I won't pay to buy it/see it/listen to it. I also don't disparage other people who *do* want to support it.
In this case, it's a movie based on an existing work where the character of Dr. Manhattan was portrayed as being nude. It's a deeper comment on Manhattan's rapidly-dissipating link to the rest of humanity. Most of the 'controversy' about it seems to completely miss the point, but at least people noticed. If they only shot Manhattan from the waist up in the movie, would people still get the point thanks to the 'subtlety' of the filmmaker's approach? I tend to think that it would drastically alter the way the message is received, and that the point would at least be muddied, if not lost entirely.
Regardless, I'm of the opinion that the best way to voice an opinion on this matter is to vote with your dollars. I've already voted with mine. :)

I'm pretty sure you don't understand the context of the sex scene in Watchmen. If you take a good look at the graphic novel itself, you will see that the sex scene occupies a single page out of the total: 424 pages. This example gives further support for the sex scene in the movie, since the movie is meant to be faithful to the novel itself. You act as if the director of the film consciously inserted this scene to attract more viewers. If this were true, we would have heard a lot more about the sex scene BEFORE the movie was released. Otherwise, the "intent" you suggested is completely invalid.
For those people who are made uncomfortable by such sex scenes, there's something called the rating system, and if I remember correctly, Watchmen is rated R. This is not an accident. Screeners have identified potentially offensive material and this rating shines brilliantly in the face of anyone who watches it. I consider that a fair warning.
In response to your friend's comments, you both seem to categorize images as either causing pleasure or displeasure, while not acknowledging any emotion between those extremes. Showing a sex scene is not purely about the carnal desires of those depicted onscreen, especially in the complex world of Watchmen. It's about putting the audience in the moment, as well as in the minds of the characters. If the characters happen to be engaged in love-making, then so be it. This moment is only a fraction of what Watchmen has to offer. Don't ask people to tone things down just because you're not comfortable with it; real life does not work that way.
And I'll end with a question to you. Did you play Mass Effect? Were you so reviled by the sex scene that you denied the magnificence of the rest of the game? Did that prevent you from finishing (or even buying) the game? I knew about the sex scene before I bought the game, but I was much more excited by the gameplay, plot, and characters than I was by the impending 30 second cinematic

I didn't experience the sex scene, since I avoided talking to Liara. She was dull. The other lass was much more interesting, but I think I chose the wrong speech options, (story of my life!). Not that there was a sex scene for her anyways (that I know of).

same.
and regardless of the context of the scene, the fact is that it is gratuitous when it quite clearly could not have been and still got the point across. I am aware of the rating system, but that doesn't mean I can't criticise them. Even movies with implied sex to a point have been rated R.

So, as long as you haven't seen the sex scene, it's not a problem? That seems to be what you're saying here. Then by your logic, you should be able to see all of Watchmen except for the sex scene. Hopefully, they will release a DVD version that just omits the scene. And in the same vein, you can't criticize Watchmen as a movie without criticizing Mass Effect for the same reasons.
But it really just boils down to your opinion and self-judgment on such movies/games. Thanks for the debate; I'm not looking to change your perspective on movies. I also do not support gratuitous violence for the sake of violence, or even sex for the sake of sex. I think we'll see more of this as the line between games and movies continues to blur.

like I said though, if I want sex, or want to look at porn, I'll do just that, there is no reason to put blatant sexuality in a film, especially if it doesn't relate to the storyline, other than to draw a bunch of perverts to theatres.

At least with the Watchmen it did relate to the story.