I agree with the op 100%
I've been washing my hair with nothing but water since I was 16, so thats 14 years.
I never have dandruff, I've gotten comments on how soft my hair is quite a few times in the past, and best of all no cancer causing chemicals absorbed daily!
Dish soap is another killer. I only use very hot water to wash my dishes, and they are always sparkle clean, and never have that film that I used to get
from dish soap now and then.
If I ate meat I would probably be using some sort of organic dish soap though.