No, it makes sense. Some people want to see the whole picture while others prefer the cropped widescreen presentation. So, if this new release was full screen only or widescreen only there would be less potential buyers.
They could of course make two separate releases with lower prices, but it would be a mess. It would be more expensive to produce I believe, and I don't think many stores would like to carry two new editions of Evil Dead... I even wonder how they're gonna get this one into stores when the stores are already full of Evil Dead dvds