If you want to use Zarath's shop, you could just delete the image code from the tpl files. There's an add-on for Shop 2.x somewhere (I honestly don't recall where I found it, maybe on bummer's site) that made a default image be used for any item that didn't have it's own image.
wGEric Store MOD 0.2.1 doesn't require you to use item images. The test/support site (link in my sig) doesn't have images for most of the items. A few of them have images, but that's totally optional and can be configured on a per item basis.