$100 up front is a big deal. For a $400 console, that is 25% more, hardly something to scoff at. The 360 controller is far superior in my opinion to the DS3, but that's just my opinion. There are many gamers that prefer the Dual Shock, and that doesn't take into account the fact that the PS4's new controller has been getting glowing reviews from the people who have handled it so far. It isn't too farfetched to think that the gap could narrow(for those of us that prefer the 360 controller, that is). To say that you don't understand how anybody would prefer a console that is at least marginally more powerful to the Xbox One, at a lower price point, without a potentially useless peripheral bundled in the box, is being intentional obtuse, or at least sarcastic.
That says nothing of the people that feel burned by MS's recent shenanigans. Sure, they've backtracked, but I don't blame the people who won't touch the Xbone, be it for principled reasons, or just out of spite.
We also shouldn't forget about MS's Xbox Gold paywall, behind which are hidden features and apps that are free elsewhere, ie: Netflix. And they still haven't said much about peripheral support, especially concerning racing wheels(which I am particularly curious about).