I agree with both persons.
Yes, the grandstand is inside the fairgrounds. Your concert ticket is your entry ticket into the fair. Just use the bar codes they text to your phone. As for parking, if you do not mind walking a block or two there are places to park for free. There are other places outside to park for only a few $$.
Yes you have to enter the gate but you don't have to pay admission. Just show them your concert ticket. However you still have to pay for parking.
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