It has been in use for over 20 years.
It's origins are similar to that of the term "Touron" which is a cross between a tourist and a moron. These terms began and are currently widely used in the resort industry and National Park Service.
It was in use as early as 1986 Yosemite National Park by employees of the Yosemite Park and Curry Company.
If you're not a happy camper, then you've just had a bad experience.