Uploadpath doesn't move file to correct path when editing a node

Issue Summary

For example:
I am using Taxonomy and I have a flat list of vocab setup called Category which displays a list box of those categories when I create/edit the node. I have a path setup like so: [type]/[term-raw] for a content type, lets call it Document.

I create a new content type Document.
Give it my title
Select which category I want it in from the dropdown list of Taxonomy terms. let's call the category 'Food'
I upload a file then hit save.
The file shows up under sites/default/files/document/Food .... as it should

If i go back and edit that node and all I do is choose a different category say.... 'People' the file remains in sites/default/files/document/Food

I don't see how this kind of behavior is a feature so that's why I am submitting it as a bug.