I have the same problem, for example subway subs images for fantasy football backgrounds and visa logos. Also many folders containing icons and other images that I cant tell where they are being used.
I get that I can hide them but I dont know what folder they are in even after looking through astro. Is there any way to find what folder each image is in, I tried to get picture details for some of them and it says hidden wtf.
I guess I cant delete the icon folders anyway but why would they all show up in your main gallery taking up space and cluttering up what you really want to see????