Alot of people, in alot of different countries dye their hair (horribly fake) blonde. Blonde only works if it is natural in my opinion. Germans aren't any different. You speak as if having blonde hair or dying your hair blonde is illegal or something.
It's not about dying your hair blonde, it's about dying your hair blonde in a horrible way (like that chick. You can still see her really dark hair).
If you want to dye your hair, dye it all the way, or at least dye it a colour that matches/fits with your own haircolour. "Roots" just looks terribad!
PS: I got fair hair myself nabb