What haydnfan said.
Plus, simaru, you don't read in the dark at all, so naturally, if you sit in a well lit room, or read during the day by the window, you are able to use a higher light setting. Not everybody has the luxury of reading time during the day, you surely can see that, no?
Many users here read in the dark in bed (crazy idea... I know....) often with someone sleeping next to them.
The PW was not made for daytime only use. Amazon built lower light settings into it for use in the dark.