Well, it's a lot cheaper to do for one. The whole thing is just a switch on a wafer over the battery.
I kinda like the knobs too... Particularly the ones with "off" for every other setting --I typically use lower illum. and usually only one step up for bright, so having it that way works best for me, off in the middle, hi one way and low the other.
The ones with the digital shit are okay, my USO's were the first for me to have an on/off and two arrows. You gotta feel for it sometimes, gloves don't make that easy.
I still really don't know why I bother with the damn illum., I could save money forgoing it, I use NV in the dark anyway. Illum. is great for dusk/dawn, where most hunting occurs, but I ain't a hunter. Habits die hard I guess.
What'd work best for me would be small, replaceable amber tritium lamp instead, maybe with a push button shutter...