Don't forget everyone gets a free autograph from one of the lesser guests, I expect they will have steady trade through the event. And those doing costumed photoshoots will also have less time at the table.
I've heard rumours in the past that Joiner has a vast stash of pre-signed photos which he needs to get rid off and realise as cash. It would explain why the dealers room guest list contains all the cheapest guests from his "Trek guests I've had before" roster.
If I wanted to be really cynical, I might suggest that people's "free autograph" will end up being a pre signed in addition to the pre signed photos he's already supposed to be giving out as part of the ticket packages.
And the hoover has been out again. For those of you who missed it, here it is.