Gawd all that jumping to conclusions...
My dd1 plays the violin, including two orchetras, does dancing an brownies.
Dd2 does flute, one orchestra, brownies and dancing.
It's all mostly during the week though, while I obviously dont mind the odd weekend activity related to it - there might be a concert, or a dance exam, or a brownie outing. All good, just not every ingle weekend!!
My nephew learn the guitar and currently does football training once a week with. Tournament very six weeks. His sister does ballet in the week. All good - my SIL just doesn't want very weekend taken up, especially as the season is September to end of June! You lot make it sound as if she locks them in a shed. And as for being selfish - it's not about wanting time to herself, but about time as a family!!
What makes you think I won't give my teenagers lifts just because I wouldn't want to stand on a football field every weekend?? I know full well that they will become more and more independent as they grow, but it's exactly those precious ten years that I want us to spend together!
And if there are people who are just not into having hobbies, but would rather spend their time at home reading, gardenig, whatever - so what? Why is your way of living life the only valid one?