Hi there,
You're right, there isn't any "weathering" etc. on these and it is intentional. My aim with these models was to get a crew on the table (fairly) quickly so I didn't go to the level of micro detailing. I have used those techniques before on some of my more "showpiece" models. I suppose the best example is my bloodbowl ogre which can be seen here: http://www.coolminiornot.com/107957
My painting style has always erred toward the neat comicy style rather than the more earthy realistic stuff. Not that either is better, just different!
All of the above said, I'm currently working on a Peacekeeper that WILL have quite a lot of weathering and battle damage on it. With models like that, that have large flat surfaces, I find it nice to add something to keep the eye interested (same reason the exe's belly is hairy. It looked too bland without).
Hope that answers the question.
Thanks to everyone for the comments, they're really appreciated.
Cheers,
Dom