Parents that don't enrol their children into any extra-curricular activity are definitely lazy in my opinion. My parents didn't do it proactively for any of me and my siblings, I was the only one who made the effort to play sports and do stuff outside of school and even then I was made to feel like it was a chore for the rest of my family. Get them into sports, dance, martial arts, whatever. The benefits of socialising outside of school and the added physical exercise is immeasurable.
I know parents who “like their weekends free” so their 3 didn’t play sport until their youngest demanded to play basketball.
I couldn’t wait to get my young bloke into karate, he’s four (nearly 5) but is starting to get into it. Auskick and Milo cricket this year!