^ in your specific instance (referring to the axe face photos), the problem is actually with the way bigcartel displays their catalog -- the images are background images so that they can easily overlay promotional or status messages onto the item photos. those kind of images are difficult to grab even on desktop browsers since the normal right-click affords no access to them.
another way to grab image urls is by pressing on one until you get the pop-up, choose copy, open a new tab, paste into the address bar, then copy the text from there into the forum text box. for some reason, you can't paste directly into the forum without the intermediary address bar step
