No.
a. Why not?
I don't like to label, but I'm generally one to consider myself a straight-edge. It's been like this since I was 12 or so, and I originally thought it was not worth getting in trouble over. It is legal in my state now, but I'm still not doing it because first I'm not old enough, and second I like the idea of being clean and I guess pure.
b. Do you judge people who do?
No. I don't think it's wrong to do. If that were the case I would hate much of my family that is similar to my age. As long as you are happy doing it, and don't try to shove it into my face, then whatever in the world you do is perfectly fine with me.