My guess is the person's age and lack of experience using a computer. People don't like change, creatures of habit.
I griped about the registration part of it because they hosed that up pretty good. Overall its easy to use but I have found a few bugs with it yet. Like one was when I purchased my gun and archery license. I had both licenses and my 2 farmland tags in the cart. I then deleted my gun license and it removed that along with both farmland tags, even though one farmland tag was with my archery license. No big deal since I caught it but clearly a bug.
Saw some spelling errors as well which just makes it look bush league. Kind of unacceptable for a professional website, you would think they'd check all of that over.
As far as using it though, no big deal. Been buying my stuff online for a while and its really not much different aside from having to print off the tags now. I see no reason to go stand in line to buy stuff anymore.