I always just use 'mv', etc. from a terminal. So this is genuine curiosity - is there something that other people do for which a Finder window and cut and paste is better/faster/less prone to mistakes, or is it just that the shell is not as familiar for them?
I just can't imagine a hacker workflow that involves doing that even once per week, much less day.
I'm not saying I don't miss Cut/Paste on those occasions, but it comes up so rarely and I feel like I gain so much more by using OS X that I just don't care.
At first I couldn't think of a real use-case that matched your description, but then I realized one that might be close - Say I want to copy some pictures in a directory that relate to a craigslist posting over into another directory. I've done that. And since I only ever use those photos once, I prefer not to import them into something like iPhoto or the like.
So that's a case for having a GUI file manager, but (back to the original point), I'm not sure it's a case for cut n' paste.