Developer of Fluid Here. Basically, this is a bug.
It stems from the fact that Google is the search provider supported in the toolbar search field. Therefore google.com URLs are currently always white-listed.
I would like to fix this eventually.
This got down voted, some comments could have been more helpful. Yes lots of new questions are poor or not up to "awesome question" standards, but not all simple questions are bad or unanswerable or unuseful.