If Amazon does not want to protect Merch images by using watermarks (due to potential sales suppression) ... then, they should consider using "in context" product views of real models wearing the shirts. This should be the ONLY product image available in the listing and its thumbnail preview (removing the flat, easy-to-steal images from the listing altogether). These images could be automatically applied to a mockup template by way of programmed displacement maps. [Do a Google Image search for "t-shirt mockup displacement map"]
Points to consider:
- Watermarks are easy to remove in Photoshop.
- Watermarks can potentially detract from sales.
- Displacement Map Mockup views ENHANCE the product listing with a real-word view.
- Displacement Maps create an almost IMPOSSIBLE to steal-and-reuse product image. An in-context "model view" is certainly useless as a source image. It includes representations of wrinkles, folds, shadows, perspective distortions, etc.
- If using displacement maps is not an option, then using watermarks SHOULD be considered as a means of offering *some* degree of image theft protection.