Seems like the whole point of this thread is to overcomplicate a simple problem using extensive concepts that would never solve the original problem.
So let's say you do raise taxes on junk food and you ban kids commercials for junk food (don't know how that will help the fat parents who watch Game of Thrones though).....
You still have inactive kids sitting on their fat @sses, playing on their phones or playing games, doing nothing.
Then they have all the sugar and fatty food removed from their diet and they still sit around doing nothing. When you tell them to go play, they will complain that they're too tired and get dizzy when they stand because their lunch time meal of three kidney beans and a slice of tofu between two slices of high fibre / low GI grain bread didn't give them enough energy to blink properly.
So parents throw their hands in the air and let them keep playing games and staring at their phones all day. They then complain to the government that it's someone else's fault their kids are all screwed up more than before, so the government introduces more lunatic laws and taxes while still not addressing the real problem.
And the real problem are the parents for being failures and not getting more involved in their kids life. Sticking a phone or a game in their face is easier and gives the parent more free time for themselves without having to listen to their kid whine and moan all day..... You know, as if they didn't want to be parents or something and being one ruins their grove.
The problem isn't about eating crap food. The problem is not doing anything active to burn it off.
If you sit on your @ss all day doing nothing physical, you eating just the basic food groups recommended will make you fat.
Obviously it's both activity and calorie consumption.
I work an office job and I've lost 10 pounds just by changing my diet.
I basically gave up sugar and bread for lunches and I just snack on vegetables throughout the work day.