I didn't make the rules, so I'm not entirely certain, but I'll try to explain the reasoning as I understand it. Please note first though, that this post isn't intended to scare you or anything - just help you understand WHY the rules, and internet safety in general, are so important.
Sooo... Let's say, you mention in one of your posts that you live in Arizona. Totally innocent, and not really personally identifying, right?
Now in another post, when someone asks for homework help, you respond saying you can't help with the answer because you're only in 6th grade. Again, totally innocent, right?
A week goes by, you don't even remember making those first two posts. Now you're in the Daily Chat Thread, in Open Mike. The subject is "What's your favorite sport?" You post saying that your favorite sport of all time is soccer, and that you've played since 3rd grade, and last year, your team won the league tournament. Again, totally innocent, right?
....But anyone who looks at your last week worth of posts now knows that you are a 6th grader in Arizona, who plays on a girls 11-13 soccer team that won a league tournament in 2007.
Over the next month, you make more innocent posts. In one, you mention your hair color. In another, maybe a Guess The Number giveaway in the Contests section, you pick 42, innocently mentioning that it's your favorite number because it's the number of your school bus this year, and 42 has been your jersey number for the past 3 years.
Let's say that's all you ever post. Not too bad, right? Let's see... We only know that you're in 6th grade, live in Arizona, play on a girls soccer team that won a league tourney, wear jersey number 42, have blonde hair, and ride bus 42.
And now if a "bad guy" is tech savvy, he can upload a picture onto a webiste that he owns. Any picture. Maybe a rainbow. Maybe a kitten. Every time someone views that picture, he can see their IP address. So now all he has to do, is PM you with that picture included in the message. It can be a totally innocent PM. BUT even if you delete it, and don't respond, as long as you opened it, he now has your IP address.
So now he can decipher your IP address... do a reverse lookup, use an IP to location tool, and find out the exact town or city where you live - BumbleGumble, AZ. So now they just have to google the 11-13 y/o girls soccer teams in BumbleGumble, and find out which one won the tournament. There's probably a team picture archived somewhere on the internet, from the news story that was inevitably run when your team won. It probably includes your first and last name, too. Just look for number 42 with blonde hair. BINGO! Now he just has to go sit outside the local school for a day, and look for the girl from the picture who is getting onto bus 42...
Even imagine how much easier it would make it to find you if you'd signed your first name on a post on a friend's profile. Yikes!
5 or 6 "innocent" pieces of information, in 5 or 6 different posts, spread over a month or two long period. You don't even remember making half of them, but that's all it takes. So the rules are meant to keep you safe. They're meant to prevent you from posting ANY identifying information about yourself. It's VERY easy to let little bits slip here and there, and think nothing of it. I know I do it all the time, often times without even thinking about it. (I'm over 18, and have all my info out there from my social/political activities anyways, so I know I'm a little more careless than I probably ought to be.) So the mods don't want anyone posting their state, city, age, school year, team names, first names, last names, etc. Nothing that can be used to identify you. The rules are there to make sure that WI
is one of the safest sites on the internet, and a site where parents feel comfortable letting their kids visit.