Why play defense?

There are thirteen 9-year olds on our 7 man flag football team. The league requires that all players play either on the defense or on the offense for the entire game. Therefore there are 7 starters on offense and 6 starters on defense with one of the offensive players also playing defense. Assuming half the plays are offense and half the plays are defense, everyone plays at least half of the game. You think that would be a pretty equitable system. I coach the defense and the question I hear the most is, "when can I play on offense?" It does not matter how well or how poorly the player is playing, whether it is practice or in a game; all the defense drools with envy over the offensive players. In the last game our shut down corner intercepted a pass and took it in to the end zone for a touchdown. He came running over to the side where I gave him a high five and a pat on the back. "Good job, man", I praised him. He looked up at me grinning from ear to ear with the echo's of his team mate's cheers still pulsing through the air and he said to me, "Thanks, now can I play offense?" I told him he was playing offense he had just scored a touchdown. He looked at me like I had recently escaped from an asylum. He just continued on to the bench after giving me that nod that kids use when adults say things that make no sense to them. Clearly, in his mind what he had just done was NOT offense.
So why is it that playing offense is cool but playing defense is well a necessary evil, at best. Why do defensive players long to be offensive players? I think it is because offensive players have power. They know what play is called, they know what they are suppose to do and they challenge the defense to figure out what the offense is doing and try to stop it. Obviously, they are dictating the terms to the defense and it is up to the defense to try to react. Some how we have come to value the act more than the force that seeks so contain it.
Is this a metaphor for the society we will live in? It seems like we admire and emulate actors, musicians and celebrities that behave in the most debauched and depraved manner while shunning any conformity to standards of moral and decent codes. Is immorality offense and virtue defense in the modern world? Has the desecration of our founding principles and contempt for traditional values become the offense while morality and religion become defense?
Maybe that explains the way we have become. Everyone wants to be on the cool, hip, POWERFUL offense, challenge the stogy, weak defensive forces of morality, virtue and religion to try to contain them.