I have never been to that particular show. However, I have attended similar type shows at other shopping malls, i.e. The Mall at Robinson, Westmoreland Mall and Monroeville Mall. I should expect most of the stuff will be Pittsburgh focused. Baseball and Football will be the most common items. At all of these type of shows I see some vendors with a good bit of vintage available at reasonable prices to fill out sets. Some of the professional vendors seem to go to these shows to sell off unsold stock that hasn't moved.
Hope that helps.
We all live in a Perry Groves World...