I read Nicole Taylor's "Schooled on Fat - What Teens Tell Us About Gender, Body-image and Obesity" recently and I think it has some themes related to this feeling of helplessness. Just as the teens surveyed knew junk food was bad but couldn't resist it, we know spending too much time on these distractions is bad but we end up doing it. Interestingly, peer influence and social acceptability seem to be involved in this too, as it was in her study. We have to get 'social' so we don't appear to be odd and 'not modern'. And the media has been a major actor in strengthening and spreading these beliefs.