Because dodging isn't by definition morally inferior to blocking. If you correctly react to an opponents swing by sidestepping out of the way, how does that take so much less skill than blocking it? One of the reasons why there are endless block-attack fights in Warband is because movement is so inconsequential and predictable.
Currently in Warband there are 50-100 players running around eachother at a constant 10-15 kmp/h while doing attacks and blocks. This looks absolutely retarded if you have any objective ability of looking at it and comparing it to anything that resembles realistic combat. Way more retarded than having 50-100 players shuffling around at a slow pace, doing quick steps when they attack or defend. It's not a rambo move, it's a simple directional step.
If you want you could compare it to people boxing in Warband and people boxing in real-life if it is so hard to imagine for you. In Warband they would be constantly strafing in retarded patterns which looks absolutely nonsensical. In boxing they would be moving slowly, only moving faster when attacking or defending. They are able to step back and forth and from side to side quickly, throwing their body around to avoid hits or create openings. And guess what, footwork is an important part of skill in boxing. You could also have an automatic system which makes you do sensible steps when attacking or defending, but that requires complex animations and takes away control.
