If they are legit they have nothing to fear, many are not.
I don't know about you mate, but i personally fear anyone checking up on me to see if they had "one up on me". There's something scarey about that, and yes i'm legit. I think anyone checking people should be made public also, in the interests of balance as i'm sure you'll agree and understand. If we've all got nothing to hide, then lets not hide it.
There's nothing wrong with 'grassing' when you see something wrong, there is something inherently wrong with looking for things to grass people on.