Nah, not unless you make some kind of public disturbance, and even then the charge probably wouldn't be gun related, assuming you have permit.
First, the signs are generally not even close to TCA compliant.
Second, except for posted property provision, there are no TCA statutes regarding carrying at a gunshow
Third, I don't know if the LEOs at the shows are on dept time or their own. Maybe some of each .. I know some are being hired by the show's promoter, and I guess some are assigned by the PD, as I usually see a police vehicle or two there.
At any rate, the LEO presence is to keep the crowd safe, not to fill jail cells. If you have no plan to remove your weapon to sell or trade, or try on holsters or whatnot, leave it concealed and don't worry about it.
- OS