Why is Dell using Optimus and AMD's equivalent on high end notebooks?

I mean it's bad enough on the mid range or lower end stuff, but on Alienware?  Besides hurting performance somewhat, it makes the driver situation a DISASTER, and this on notebooks where you know people are for sure explicitly going to want the newest drivers from Nvidia or AMD.

My understanding is the "3D" screen Dell disables Optimus...don't want "3D", or to have to pay extra for it, but I hope that means Nvidia's normal drivers would install on a system with a "3D" screen with no hacks? 

I know a lot of people avoiding Alienware because of Optimus, and lots more with endless threads trying to deal with hacks to get drivers on because of it...

Why isn't it at least just OPTIONAL so you can use normal drivers?