why do many "disrespect" Kendrick?

It is a phenomenon, of course not just here but on all boards, why do people go to the IMDb discussion of an actor just to disrespect them?

For example just a few hours ago user 'dgirwin1' wrote, " Anna Kendrick has no charisma. Her acting has always been awful, even before she starred in Twilight. How she keeps working is a mystery. And she claims to be a Star Wars fan? Do not let this fool near a pop-culture touchstone like Star Wars. "

That is just plain mean. Why does someone do that? If you really think that negatively of any actor why visit their page, and why not just choose to NOT see any of their movies?

What kind of mental deficiency makes a person feel compelled to disrespect someone they don't even know? Now I am not a big Kendrick fan, I would never go see a movie just because she is in it, but if she is part of the cast and it is otherwise a good movie then so be it. She has chosen to be an actress, if she gets roles who are we to say she doesn't deserve to work?

Suppose 'dgirwin1' is a plumber? How appropriate would it be for some of us to go to his workplace and say "He is a terrible plumber and I don't like his attitude, please don't hire him anymore?"

Doing that would make as much sense.

..*.. TxMike ..*..