Game art not moved on bulk edit platform change

[Former user]

Somehow I ended up with platforms "Arcade" and "Mame" when I would have only expected to have one platform for my Mame games. Anything games got split between the two somehow. So, I selected all games in platform "Arcade" and did a bulk edit on Platform to change them to "Mame". That cleared out my "Arcade" platform as I was hoping so Mame platform would have all my Mame games in it. however, I noticed most game art was missing after doing this and found that I had to manually move all my art files from all the Arcade art sub folders to the ones under Mame. I guess I was expecting that the bulk platform change would have done that automatically as part of the platform change.