Sroogle is specially useful when googling via TOR. Otherwise google (and others) block queries thinking you're a bot (or maybe not because of that...) and ask to fill a captcha over and over again.
It's probably because there is so much traffic coming from the Tor exit node. Google just sees it as a huge amount of traffic coming from a single source.
At work, once every month or two someone in the building must be doing something that is really hitting Google because every Google search will require a Captcha for a couple of hours.
It could be a manual exception. I doubt that Google has the time to track down all Tor exit nodes or work ISP IPs and flag them as 'not spammers or bots.'
