I go to the NARBC in Tinley all the time; It's an awesome event! Typically the huge line you see is the line to get into the show itself. The ticket line tends to move rather quickly, but I would highly recommend getting your tickets via PayPal if you're not going the VIP route. I purchase my tickets via PayPal, and I just go to the pick-up table on the far right to get my wristband.
I usually get there a half hour or so after the start time, and I'm in within 10 minutes...and that's with three teenagers ☺️