I don't feel the shortage. Yes in tourist destinations or Holidays you will need reservations, But if you are just looking to getaway there is always a last minute spot available.
Now if you're trying to go to your favorite place in a popular area you maybe out of luck.
But if you just want a decent spot and are not afraid of State Parks and are willing to pay commercial prices you will be able to find a site.
Too many times people limit their options with their own hang ups and are not willing to be adventurous and just go.
