You'd get a similar scenario Mark, I cannot tell you what the Advisors have to do exactly regarding the image queues? As it is on a "need to know only basis" and Mentors don't have direct access to such knowledge.
Though assuming a dodgy image snuck through (and somebody reported it) it would be sitting there in a queue anyway so they are playing on the side of caution it's automatically held in a queue first.
Unfortunately not many members actually report posts anyway and a lot of spammers would also try cheap tricks if they were given the chance. Also the more devious could probably could alter the image after a set period of editing time if they were all automatically allowed.
Though I can understand your frustration of waiting... if you want to help somebody and their image is still "pending".