It is often played in college settings or where young wizards and witchs congregate. Strip quidditch often leads to more raunchy magical activities. Due to a court ruling in 1907, playing of strip quidditch by those over 45 is ilegal. Anyone caught playing is fined and stripped of magical powers.
Ron: No, why?
Harry: We were playing strip quidditch!
Ron: You lucky sod!
Harry: I've been scarred for life!
Hermione: Why, Harry?
Harry: I've just seen Professor McGonagall playing strip quidditch with Hagrid!