So, I was seeing Jake's point completely (while still not agreeing considering the mentioned issues and my own opinion and so forth), but then:
I know not just 13+ kids play on this site. My 9 year old sister plays on it everyday. Besides, the 13+ thing is just for the account.
And you let her?
How is AG irresponsible in this context, because all I can see is a big brother doing a bad job at protecting his sister from the "harm" he himself is pointing out!
Now, let me put this in perspective:
If you are out shopping with your kids, or your younger siblings or other smaller children... Who would then be responsible for those children? The supermarket, that is just there for you to pay for stuff you need? Or you, considering it is your crotch spawn/your fellow crotch spawn/crotch spawn you are looking after?
If you are at the library and the kids are noisy and tearing out pages, is the librarian, who would backhand your kids if they wouldn't get sued for it, responsible for what the kids are doing or are you as the parent/sibling/caretaker responsible and thus also able to backhand the kids for ruining precious materials?
If a kid brings a porn mag or a dildo or a (n unloaded) gun, a mag/dildo/gun they have found at home, to school, is this the fault of the teacher, who will have remove these items and make sure no one is somehow harmed or going to tell their parents or something similar, or is it the parent that let the kid take those things to school, either without removing it or checking or by simply enabling them to find and reach such items?
Because what you are pointing out is that AG is at fault for having ads you don't agree with, and that it is their responsibility to take care of your sister.
So, while I can see your point that oh-no-almost-almost-naked-women-on-a-site-children-can-access, it is not something AG can do anything about. Or should, for that matter.
The ads are not breaking the rules of this site. They are not breaking the pg13 rating they have put on themselves. If they decided to do anything about it, they would lose ad revenue and thus money. Because they are simply being paid to have an ad firm how their ads here. They have no say in what the ads are, beside being able to tell the firm that they would like the ads to at least be pg13, and keep the right of complaining of any ad includes malware an viruses, and that is it.
Go complain to the firm. Make your own firm. Be a good sibling or parent and make sure the place your kid or sibling ventures to is safe, or do something active about it, instead of expecting others to do your job.
Or sell your kid to AG, then they will be their responsibility. And they would doubtfully let them play on AG unsupervised either.
Now, if anyone else should be wondering about my stand on this after all that rage, let's take it again, but without the passion:
Parents are the ones responsible for the kids, unless they are handing over this responsibility to a caregiver, for example a school. As such, the responsible person in the children's life should be the one at fault for the kids accidentally "harming" themselves, or getting lost, or ruining public material.
I am aware that some parents are somehow oblivious to this responsibility, but that doesn't mean that everyone should cater to their needs, because in that case, I am going out to get some crotch spawns and then demand that I am made king of the world. Because I can. Because I have kids.
So. If the ads make their way directly into the sensitive eye of your child, either monitor them to make sure what they are playing and clicking on (you should be doing this anyway), or at least put up an ad blocker, so those relieving but somehow socially acceptable ads does not make their way to your computer screen.
It would most likely also stop you from getting vira when your kid decide to click everything everywhere.
... Yes, I am done.