The beach ball is one of the show center markers for the Blue Angels. It (usually) pairs with a large Coast Guard tender to mark the centerline perpendicular to the beach (not the pier). In the absence of the tender you can draw a line from Hooters to the beach ball to get the centerline for the airshow. Of course that parking lot is filled before the sun rises on show days.

Also, the corner car show is quite the sight. C1 through C8 Corvettes on display. Easily over 100 Corvettes (probably many more, I got there at the end of the show as many were leaving). The variety of engine sounds was awesome. I'll definitely be coming back next year for the full show.