I don't want to have to turn brightness to 0% every now and then because an accidental slide on the device has put it on again.
Also it's a personal choice for me to not have my kids read in a 100% dark bedroom with their face only lit by LEDs. No matter if it's a blue LED, orange/yellow LED with a better light spectrum or AmbiantClearGoodSomething LEDŽ.
A bedroom reading lamp makes a more diffuse and balanced lighting in the room, than an ereader which creates an discontinuous lightning: ereader 100% lighted, walls 0% lighted.
I completely respect your opinion @JSWolf, but I don't want this for my children: