I'll let the owner of the Internet know ;)
The Internet itself is a part of the public domain.
By this I don't mean that it's the Wild West, but the rule - "if it's not illegal - it's legal", does apply.
It's your responsibility to take your own content out of the public domain - through copyright for example, or through a robots.txt
Either way, you have plenty of tools to stop Google - it does honor robots.txt
Simple example - open any book from your shelfs and see if the publisher "assumes" that his book should not be re-published without authorisation, or if the very first page is filled with copyrights and trademarks. It is the publisher's responsibility to indicate that the book should not be re-written and it's your responsibility to indicate that your content should not be spidered.
Me - I'll take a gallon of that sweet, sweet (and free) Kool-Aid, thank you very much :)