For one thing, just because a lot of kids are immature doesn't mean that they have a license to break the law. Joking obviously isn't a violation of the law, but breaking into private e-mail accounts is (18 USC 1030).
For another, Mark had already been formally disciplined by the Administrative Board for Facemash when he wrote these, so he clearly knew better.
Aruging that Facebook has the right to misuse people's content just because they provide it is clearly wrong.
In addition, there are five people including myself who ultimately filed legal action against Mark and/or Facebook, Inc. because of what happened at Harvard.
Lastly, at roughly the same age, I ran the same core product at the same time in the same place with the same name with the same people's information, and I didn't do that. I didn't joke with my friends about it, I didn't make fun of my users, I certainly never intended to abuse people's trust, and I never did. One of those users was Mark and I have his SHA-1 password hash sitting in my database, as well as his cell phone number--but I'm not going to share it with anyone, nor have I ever. Clearly it's possible to run such an operation in a different way than Mark.
"Call a spade a spade" indeed.