I don't think it's a terrible idea but these are generally 'boring' hobbies to include on a CV. Your manager would not care if you masturbated in your spare time or if you decided to watch the cricket with your friends. You do not have to be specific with what you do with friends in your spare time, being explicit like that would probably be more suitable on a dating profile. Simply say you like to wind down the week with friends after work, or something else along the lines.
What IS good to put under your hobbies section are things that are relevant to your role, so if you work in retail, you could perhaps be blogging latest fashion trends. If you don't do that, then take it up as a new hobby.