Around me you pay $10 to get in the door of a gun show.
Gas and depreciation on a vehicle for 60 miles is $30, so another $60 there. I would be VERY surprised if you save $70 on a $600 gun at the gun show. Maybe $10-15.
You can play one dealer off another if you are comfortable with that sort of thing. I lived in places where all trade is done in similar open markets for long enough that I am, but even then you won't save much.
You go to a gun show for the other stuff.
Finding a large crowd of people who say things like "excuse me" is worth it IMO.