Gilbert Munch said:
But just so you know, I'm not in any way justifying that. I am, after all, only human, who has other needs as well as entertainment.
Okay, I'm not going to try to justify this on costs to society, damage to industry, disrespect of copyright holders, etc, because you've made it quite clear you're not old enough or mature enough to care about that kind of thing just yet, all you care about is you. So moving it to that level:
Your first problem is that you think your entertainment is a *need*. Get that idea out of your head right now, because it will cause you extreme pain later in life when you have actual needs that have to be fulfilled. If you place entertainment up with actual needs you will simply make yourself miserable when you have to choose between it and something else. Remember that it is a desire, great to have fulfilled, but livable without, and you'll actually find life is a happier place.
Second, you're being short-sighted. You are choosing short-term benefit for yourself without fully examining the risks. How hard would it be for a publisher to put out a "pirated" version of the game on the public sites that used the DS's wireless capabilities to essentially "phone-home"? Once they got a certain number of signals from a particular DS unit, it would then be fairly simple to send the cops around and have them confiscate your DS, your games, and apply significant fines to you and your family (and beware, with the DMCA in place, those fines are *nasty*) This means you'd be without your DS, any games, your parents would be loathe to let you near one again, and it would make your home-life very ugly as people around you fought about money issues. Remember, more families and couples fight over money than anything else. Bringing that risk onto yourself and your house for a few hours of entertainment just isn't a good cost-benefit plan.
And of course, as other folks have mentioned, when you pirate the games instead of purchasing, the developers have less reason to bother working extra hard to put out good games. Might as well just put together another bejeweled clone. So unless you really really like bejeweled, it's not a viable strategy if you want to get the most entertainment out of your DS.
One final thing, working for your game is actually good in a number of ways. First, there's the anticipation it builds as you work toward a definite goal and are getting closer. It means the game seems that much cooler when you finally do get it. Second, when your parents see you working toward a specific goal like that, they will be far more impressed and proud than if you just have it. And who knows, if you let them know what you're working toward, you can sometimes luck out and find you get it as a gift