Remove catalog thumbnails from merged files?

I used the batch remove option to get rid of all catalog thumbnails for objects. They drive me nuts, they draw too much focus from other objects, and they make me wary of using them "just in case I upload this somewhere" which I don't like doing because it limits my options (I also remove theCC icon for that same reason, and so the thumbnails are annoying because they make it very clear content is CC).

But I have a TON of Peacemaker items- they make a lot of nice mid-century stuff that I'm obsessed with- and none of the icons remove when doing the batch fix on them, even if it tells me that it fixed the files. How do I remove them from batch packages?

I tried opening the packages and just deleting every "Catalog Thumbnail" entry, but literally nothing happens when I do that. It doesn't actually delete anything.