As with everything else, it doesn't apply to every adult all the time. That said, most adults need to work in order to survive. Couple that with the fact that

As with everything else, it doesn't apply to every adult all the time. That said, most adults need to work in order to survive. Couple that with the fact that most jobs these days are done either directly in front of a computer or using some screen-enabled device, and it's not hard to see that most adults will have been staring at a screen all day most days.