I don't think it's much of a loss. It's only thin vinyl and, unlike the One itself, looks rather tacky.
I already have a very small laptop bag that I use as a man bag (yeah, I know) but handily it has a laptop pocket into which my One will slide very nicely.
If you really want to carry your One around in a sleeve, I reckon you'd be better getting a neoprene sleeve. I have one for my MacBook Pro and not only does it feel much nicer than vinyl, it provides quite good protection.
One thing that is a bit strange about this is the inconsistency from one One to the next. Some have Intel SSDs, some Samsung. Some have a 2200mAH battery, some 2400mAH. Some have a second soldered mini PCI Express slot, some don't. Some have a sleeve, some don't.