In a multi-store Magento build each store view will have a corresponding cache folder in /media/catalog/product/cache, e.g. '1' for store '1'.
In the website I am currently working on we have an ever-growing list of store views and I can't help but thinking I need to do something about the ever expanding list of cache image folders. The images are always the same regardless of the store view, so the extra cache folders really are duplicates. I would prefer just the one set of cached images, in part because this will make the product quicker and the bandwidth lower (a customer swapping a store view will not require an extra set of images to be loaded).
So far I have done little to 'fix' the per-store product image cache. I have also not found any other writing online about this 'problem' and how to fix it. Does anyone have any idea?