I know this is going to be a naive question but...
I am not a stamp dealer of any sort, and I have often wondered why dealers tend to leave the little "floating chads" in place.
There are some along the top of this stamp:

Now, if it were me selling it, I'd take a little pointy thing (geometry compass) and snag it off. Who would know? And why keep the flimsy little things around?
I know a lot of you blog readers are dealers and can tell me the obvious answer to this naive question.
(Incidentally, some of the most beautiful engraving can be found on Canada's revenue stamps.)