Or they were simply misguided and confused because, normally, returned redemption cards are not listed here. In this case, where it was separately printed card, or something that is not simple to reproduce (such as writing "R" on it, punching a single round hole, or clipping a corner off), those have been permitted. It's a fine line, and some just don't understand it fully. I doubt it's anyone trying to change history.
-- Dan --
Note: Please see my profile for more info regarding trading (section updated 3/4/2024). I have added a large portion of my inventory to the site, and currently have trading turned on (details are in my profile).