The Higgs Boson was confirmed based upon a statistical observation and now most particle physicists believe the standard model to be accurate. I don't see a problem with claiming something is a law if the statistical analysis supports the claim. Even our own existence is based upon statistical interactions with photons. If you don't believe that, turn off all the light in your bedroom tonight and tell us tomorrow if you could still see yourself in the mirror.
I think people use "laws" out of optimism--they really want to improve our predictive powers and "wish" that they could come up with a black-or-white "law" to help out. Of course, as you say, the world is shades of grey :)