On an overcast summer Friday with rain in the forecast, beach parking lots in Seaside Heights charge $10 to park. Saturday may be a $30 day or a $5 day – it all depends.

News 12's Brian Donohue has always wondered who sets the price in those lots, how they do it and how it all seems so coordinated.

On today's "Brian's Positively New Jersey,” Brian bounces from lot to lot for a look at an example of pure capitalism and a colorful, perfect picture of the law of supply and demand at work.