I think it's just that some folks are "in the biz" or "hoping to be in the biz" etc. which is why they're using aliases here, and therefore are sometimes camera shy. One of the wonderful things about Internet message boards in the anonimity of it all, which you give up some of meeting in person and more of with a photo record of it all.
Obviously (see photo @ left), I've got no such troubles myself, but I've got no sort of performing, or official theater biz aspirations other than this here site.
I don't think anyone would have dove under the table had there been cameras there, many just preferred not.
My 4 cents,

Rob