Why?
Laziness, a lack of common sense, and no basic repair skills or knowledge of the use of tools.
The generation we are discussing here is the condo generation -- they don't even possess the skill set to live in a house. They grew-up in a house where mom and dad cut the grass, changed the oil in anything with an engine, and fixed most things that broke. Mom and dad didn't require them to help and learn because the kids were too busy playing "sports" and collecting participation awards and just didn't have time to help around the house. The kids who didn't play sports didn't have to help, either, because they could convince their parents that their (sport-playing) friends' parents didn't abuse their kids by making them do things that only adults are supposed to do. These kids now live in condominiums where almost everything is done for them, and if it isn't done for them by the condo association, they hire somebody to do it. These kids don't even own a tool box or a ladder. It's a sad thing. Some of them, though, do go on to buy a house and learn to do some things for themselves -- this is the new-camper pool.
I am a plumber, and I run about ten service calls a day in the Washington, DC metro area. I am amazed (but happy) at how many people are out there who can't change a lightbulb -- let alone, change a toilet flapper. In all of my years doing this work, I can only think of two customers who were RV owners, though I am sure there are a few more than I know about.
Campers are, in general, self-sufficient people who aren't afraid to get their hands dirty or sweat at someplace other than the gym. Campers are people who never needed a participation trophy.
Bruce