There is the old saying that today's luxuries are tomorrow's necessities and it certainly applies to RV's. I talk to people at campgrounds and many are wanting to go to a larger MH from their current 28-35 foot one or put in a 42" TV in their MH or 5th-wheel, and have to have a dry bath with a bath tub. Got to have AC all the time and cannot cope without a microwave and a king size bed.
Having never experienced the outdoors they want to go "camping" but have no concept of even how to sit an listen to the the sounds. They have to have their MP3 players and boomboxes and motorized ATV's and trail bikes so as not to have to walk anywhere. They take their home with them and never really travel.
Slide-in campers are much closer to the MH end of the camping spectrum. I have a lot of respect for the very few families I know that actual take their kids camping with backpacks and sleeping bags and small alcohol fueled camp stoves.
But people doing this in the 1960's and 1970's in California where I grew up were treated with derision as being hippies and kooks and somehow anti-American for not having a big Winnie or Airstream trailer. It has not really changed at all, only gotten worse.