As a campground owner, you can't really advertise, "No crappy campers, please." Because "crappy" is in the eye of the beholder.
So it's a lot easier to just say, "No trailers older than 20XX." Then if someone really wants to come, he can send a pic and probably get in.
I'm sure the campground owner doesn't want his campground to turn into a "trailer park" (read "trailer trash").
1988 Coleman Sequoia - popup (1987-2007)
2012 Roo19 - hybid (2012-2015)
2016 Mini Lite 2503S - tt (2015 - ???)
2011 Traverse LT, 3.6L, FWD
2009 Silverado Ext Cab, 5.3L, 4x4, 3.73
2016 Silverado 2500HD Dbl Cab, 6.0L 4x4, 4.10