Try waiting in the preregistered ATTENDEES line for an hour and then be told "we don't have you in the system"
Then we go all the way home and I check my email (which a little voice was telling me to check before I left this morning but I ignored it).
Sure enough there's an email from the Sponsor who gave me passes with instructions to wait in the EXHIBITOR line and to call his cell if I had any problems.
Lesson learned: ALWAYS LISTEN TO THE LITTLE VOICE
