Well....in simple terms junk food has many negative advantages:
First, junk food will greatly affect our child obesity problem. In these tough economic times, people need to cut costs. As we all know, a 99cent McDonald's burger sounds a lot more appealing then $5 apples. Even I have to agree with that
Two, junk food will greatly alter the produce industry. If you look at how much farmland there is in the US, you will find very little. That's because kids are snacking away on chips and the farmers have very little business in this generation. Global warming doesn't help either, but kids need to be enforced to eat right.
Three, Junk food just tastes good. It's engineered to be delicious. In sure that you can't resiste your favorite piece of chocolate, right? Well, kids can't either. They just eat it all the time and greatly impact their food pyramid.
Now on to parents...the truth is that they know it's bad for them. Anybody who smokes knows that it's bad for you. Anyone who does drugs knows it's bad. So why do they do it? It's because of addiction. I know that there isn't cocaine in cakes, but kids just get hooked on it. No matter what some parents do, kids just want junk food. Now, here's the thing. Not all parents give their kids junk food. I can't give you an exact number, but at least 2/3 of the kids in the US are properly dieted. The other 1/3 is just probally giving into their kids or saving money.
In conclusion, Junk food effects our health, our produce, and our tastebuds, and a few parents just give in to the evil's of junk food.