I can see it being a problem for a lot of people, depends how sound your parents are.

Im 24 (tho wish i was younger, lol) and my parents are quality, dont ask for any money, dont care who or how many birds i bring round (Mum thinks its quite funny and think Dad likes a good stare, lol), and the way the house is laid out you dont actually have to have any contact with ma parents if you dont want.

Couldnt afford to live the life i live and have a decent place to myself, and no way would i live in some shitehole, so im sound here.

Tho i can understand why people move out, if had intrusive/wanker parents like some, or even if the house was laid out different, im sure idve went long ago, but as long as birds here isnt an issue in any way, im staying till i can afford somewhere decent.