We did not pay extra for the cabanas, but I don't think there is a charge for it, just subject to availability. We were only two people, but I did tell them it was for our 40th anniversary.

to fritzks -- There is not a day pass charge, but there really is nothing there other than the restaurant, the cabanas and the beach. There are very nice restrooms there, but don't remember whether there are changing rooms or not. There are some outside showers to shower off sand from the beach. There is a charge for the chairs, regardless of whether you eat lunch or not, although I really don't know what it is. Probably around $30 for 2 chairs and 1 umbrella. Certainly, you can rent chairs for the day and eat lunch in the restaurant, which is what most people do. It's kind of a hike to get there, so I personally wouldn't go unless I was going to eat lunch also.