Because anodizing is a surface treatment. Yes you're increasing the thickness of the natural oxide layer, which is a good thing, but at best anodized parts offer moderate wear resistance. Fine for bits which can just sit there looking pretty, but I'd never have anodized cranks.
Could look good if done right, I'd concede that, but how long?
Impractical why?
The cranks will scratch no more than any other cranks. And will still look great.
Because anodizing is a surface treatment. Yes you're increasing the thickness of the natural oxide layer, which is a good thing, but at best anodized parts offer moderate wear resistance. Fine for bits which can just sit there looking pretty, but I'd never have anodized cranks.
Could look good if done right, I'd concede that, but how long?