I recently installed Arch Linux on my Pi Zero, it also uses FAT32 for the boot partition. I did the initial setup the way you described. Check out https://archlinuxarm.org/ , it's pretty great.
I believe it's a remnant from the past, before ambient light sensors and auto-brightness became commonplace. People thought #000000 on #FFFFFF put too much strain on the eyes. Fortunately, it looks like web designers are moving away from that—a good, unapologetic example is Bloomberg's website: https://www.bloomberg.com/.