WTF with the Thumbs Down???

Why do people bother looking at photos/vids and then take the time to Thumb Down them???
I don't get it....who does this....I'm thinking it's probably someone who has never posted their OWN material.
Who doesn't want to look at a nice pair of tits or a pussy???
Why do they even waste their time looking at porn???
I just don't get it!!!!!