I don't even see how that is enforceable, I mean if you upload to a site are you also uploading to googles server at the same time? How do they even get a copy to claim the irrevovable wordwide copyright?
also somethings that I could upload I might not own the rights to give away, this would include uploading something that I had copied from elsewhere, or it might include work, If and when I've done freelance work online it's always had to be me making work and selling that work and associated rights to the person who buys the work, google are not involved. the same as if I upload work from my job the work there is the property of my employer, I again don't have the right to give that to google, so how would they ever claim it to be theres?