Forget the beach tags. If you just want to sit on the beach for a day, free, head to Strathmere, any of the Wildwoods, or Atlantic City. Their beaches are free.
Also free: the beaches along the Delaware in Cape May. That includes Sunset Beach and my favorite, Higbee Beach. Sunset and Higbee are also dog-friendly. Are we surprised I love them? Emily, my dog, doesn't like Sunset, though. The consistency of the sand hurts her paws.