Discussion: 'clean' books?

So... I hope I'm not stepping on too many toes here. But Kelly from Effortlessly Reading recently made a post about cussing on your blog (even words like 'damn' or 'hell') and that got me thinking about YA and what kind of content is acceptable, not just on blogs but in the books themselves.

Sometimes I see books advertised as 'clean' fiction or clean YA, or blogs as clean or family friendly. And somehow that rubs me the wrong way. I suppose 'clean' here refers mostly to issues related to sex, language, or drug abuse and the like. I don't know what exactly it includes because I was never all that interested.
On the one hand, I get it. There are quite a lot of bloggers who are mums and don't want their kids to stumble across a certain type of content in books or on the internet, so to them 'clean' signals 'safe', I suppose. While I understand the sentiment of wanting to 'protect' your children, I can't help associating the label 'clean' with 'fake'.

It makes me think of stories featuring teens or people in general that just don't seem real. People cuss. People drink. People have sex, also some (though by far not all) teens. It's simply a fact of life. People cuss when they get angry. People do stupid things. There are teens in terrible, abusive situations (alcoholic/abusive parents or boyfriends, peer pressure, groups that aren't good for them) and the idea that their stories, their voices and lives, are somehow unclean and shameful makes me really angry. It's like they are not worthy of being heard or understood. It's people looking away because something is ugly and incongruent with the way they want to look at the world.

I think these books especially are really important! The world isn't white picket fences and happy families. There are teens in horrible and abusive types of situations, and they should have the possibility of finding people like themselves in books and maybe gaining hope by reading about these characters' struggles and feeling like they're not alone. I'm thinking of books like Pushing the Limits or Eleanor and Park as well as a lot of Ellen Hopkins' or Laurie Halse Anderson's work.

I'm not saying there should be loads of drug use and explicit sex scenes in YA, but sometimes the author's agenda is just so obvious when there are lengthy/preachy contrived discussions between teens in the books about how it's better to wait or how some girls are so slutty (because it's okay when guys do the same thing, right? *eyeroll*). Sometimes there are also religious overtones, and that's just something that I personally have a problem with. I don't mind reading about a character who is a believer, but please don't try to moralize me or convert me or otherwise shove your beliefs down my throat.

I also don't think that by trying to keep your kids away from 'unclean' books, you are protecting them. The idea that kids don't come into contact with these issues in real life and at school is an illusion. And if they really are that sheltered, I think it would be important to at least have read about those things in novels. One day, these kids will enter the real world woefully unprepared.

I could go on a bit longer about this subject and open a bunch of new cans of worms, but I think I'll leave it at this.
What do you think about the topic of 'clean' books? Have you read any that were advertised this way? What was your experience? Am I being unjust or prejudiced? Am I misunderstanding the agenda? I'd really love to get some opinions here!