You're right, just because you can turn an amps gain up to 10. it doesn't mean you need to, or should. Dimebag Darrell (R.I.P) springs to mind instantly, it just sounded like someone strumming white noise.
On the other hand, take Gary Moore's Parisienne Walkways, OMG the world would be a lesser place without distortion in that case and he's driving that amp fairly hard, that's almost like the epitomy of "tone" in my opinion.
I agree, a little goes a long way, but to say "when players use the fuzz pedal tone is not even in the equation"...nope, you should retract that immediately;-)