First and probably most importantly, they may not be able to pursue their career or hobby of choice while living with their parents. As someone who grew up in a

First and probably most importantly, they may not be able to pursue their career or hobby of choice while living with their parents. As someone who grew up in a small town, I basically had no choice but to leave if I wanted to do something that I'd enjoy with my life. My parents, on the other hand, have careers that allow them to live very comfortably in more rural areas but wouldn't be paid commensurately in a big city, so it just wouldn't make economic sense for them to try to come along with me. Second, moving out gives you an opportunity to see more of the world. Visiting a place is not the same as living there and will never give you the same depth of appreciation. It's also a hell of a lot easier to socialize with your own age group and demographic in London or any other major city than it is in a more remote or suburban neighborhood city. What I personally think should be more common might be the reverse of what you're proposing. If I could afford it, I'd get a bigger house and let my parents move in with me when they retire (if they wanted). This means they'd also be able to sell their current home and pocket the profit (or invest it), easing their retirement.