Have you ever seen people/group of friends in the bar or at other social occasion, taking out their phones and start fiddling with Facebook for hours? I've seen

Have you ever seen people/group of friends in the bar or at other social occasion, taking out their phones and start fiddling with Facebook for hours? I've seen many. On the upside, i think it does help people connecting with their friends. As much as it does, it's a site where you see your friends' photos, that's about it!