Video games are meant to be fun and entertaining. They are not meant to take over your life. Most of us who play these games, know how addictive they are and how time 'flies' whilst playing them.
I am an adult with responsibilities, and therefore can't justify spending hours having fun, although it's brilliant to while away a few hours on a saturday, doing nothing but 'shooting characters' on BF3.
My newly adult son and his friends do spend too much time playing video games. Parents who don't understand the fun with video games worry about the amount of time spent playing them. Though I agree with you, they are better for our brains, than sitting like a zombie, binge watching TV.
Parents especially worry that our children are missing out on social events or social interaction (even though they wear headphones with mics, to communicate with their friends whilst gaming, you can't beat playing a game of 'kicking' a ball around, whilst being in the same room/field as your mates...