Plausible deniability is why they would run it, the raids are purely a media stunt, theres no way under either EU or US law that anyone can be successfully prosecuted for the effects of running a exit node. Any self-respecting person with half a brain cell would easily walk out of court then sue for damages, defamation of character, wrongful arrest and false imprisonment.
That all said, a persons defence is only ever as good as the person defending them, on 6 occasions I was told to "Plead guilty" as I had no chance, all 6 times I dismissed my solicitor and represented myself... I walked free from court on every occasion.