They often said they didn't do that for themselves but for smaller artists who'd be literally starving if not for royalties, Jaymz said that lots of musicians would come to them and say: "What you're guys are doing is pretty great but we can't do that ourselves, our audience will crush us", Metallica themselves relied heavily in piracy in the early days with bootlegs, demo tapes and stuff, that was what made them big enough to release their first record in the early thrash scene when no record label in US was willing to.