I seem to recall that up until the Black album Metallica had a raw deal with Elektra. Even though all of their albums were gold or platinum they were making dick on royalties. So they put out the "One" video, became more commercially viable, watered the sound down a little and hit the mainstream a few seconds before "grunge" takes off. In the wake of that happening, they get a much bigger fanbase. They were sick of not getting paid like a band of their magnitude should. I think that's where their anti-Napster shit came from. Wouldn't you be sick of getting ripped off?
That being said, I think most of the stuff since and partially including the black album sucks pretty hard. They've changed there sound to be reminiscent of whatever's hot at the time (much like the Who back in the day) and all of the mugging and "fuck you" posturing won't change the fact that they're artistically inert. They can still play the fuck out of their instruments and sound like Metallica - it's just that the music isn't original anymore.
Working with Bob Rock for years is a bad idea, too.