What I meant, although I guess it wasn't clear, is that from my own experience a vandal is many times not what you expect him to be. Sometimes, he's some guy with glasses who posts on Hacker News. And sometimes, that vandal is not a he, but a she. I've seen it all. :)

I really appreciate the brutal honesty of your initial comment! Of course there is a vandal in every single one of us and those who say otherwise (or downvote) are in denial.

That may be true of many, but certainly not everyone. I find most vandalism to be pretty morally reprehensible, since it does damage to another person or to society as a whole, for no benefit besides momentary enjoyment. I have significantly more compassion for a thief than a vandal. (Of course, these feelings would be somewhat proportional to the degree of damage caused.)