>>red_tr+(OP)
Not a lawyer, but from how I understand it the German courts argued that if you don't use any technology to prevent web crawlers from accessing the pictures on your website you need to accept that they are used for preview images (what the Google picture search technically is) as this is a usual use case.
>>red_tr+(OP)
Fair use is just a limitation of copyright in case of public interest. Europe has very similar exclusions, even though they are spelled out more concretely. But they don't make this particular issue any less opaque.