Do you not think that it's terrible UX, to have cmd+x followed by cmd+v for cut and paste in some places and cmd+c followed by option+cmd+v for cut and paste in others?
If you mean cut text and so on, it doesn't match because they're not the same thing. When editing a text document, if you cut some part, it actually goes away. If you saved the document at that point, that selection would be gone.
On files, if you cut a file on Windows for example, nothing happens. Until you paste, no operation is done. So it's not the same thing, and I think the way Finder handles it makes more sense.