Has anybody stopped to consider the printing process at the time?

The colors and pixel sizes weren't much better than black-and-white. There was no room for subtlety like anything approaching skin tones. And getting a good brown next to a heavy black line was very hard to do.

I always thought the only reason Superman's hair was black and his eyes were blue, was because black ink was easy, and blue was the only color that didn't fade to black in the smaller frames of a comic book.