You would be more than welcome to join Escapees. However, hopefully you will also join the Escapee experience and fellowship. The Escapees are a wonderful group of people who not only have campgrounds but, have social events, Escapades, Rallies and Chapters throughout the United States. The Escapees have a mail service which is large enough to have it's own zip code! They have a CARE center in Texas, great magazine and super members who as a group and individually volunteer for virtually every cause you may consider.
Bottom line is this is a wonderful group of people and you will find your missing out on the Escapee experience if you just join for the few parks they have around the country.
Here is the link to the web site: http://www.escapees.com/index2.asp