I will say, however, whenever I go to conventions, I get a photo taken with the celeb and then have them sign it. To me, that's the ultimate thing to have done, but this can definitely be an exception.
This is hard to do with Stan. They make it very clear that no pics are allowed. You have to try and sneak a shot in. They don't want anyone taking pics of Stan or him signing anything. It's all business. They charge extra $5 for a COA and a lot more for a photo op.