What a strange response. Anything is a track if you only do that one thing. The point is that having diverse life experiences that challenge you make you a much more well-rounded person that can adapt and handle difficult situations.
How is working at McD's more "diverse" than playing soccer, or even tinkering with a computer at home? It's only "better" in a very specific value system, that of the American lower middle class
Or put differently: the cliche thing that every teenager does in every American movie is "diverse"? How?
As far as getting a job, I have to say it benefited me quite a bit. I was already tinkering at home (I've been programming since I was 8) but getting a job before I left home did many things for me. I got to see how things are for a lot of people in the world around me. Some people need this shitty job. I was lucky enough to be able to do it because my parents mandated it, not because I needed to make ends meet. That gave me an enormous amount of perspective and humility. "This is how things could be for you." It gave me the drive to want to do better than working in fast food, and it gave me compassion for the people who are in that situation. Compassion that, to be frank, a lot of people I've met who have not done customer service or shitty jobs lack quite a bit. Secondly, I had to get that job myself. My parents didn't pull strings, they made me go out into the world, do applications, "sell" myself, etc. It was a growth experience. The world isn't going to bend to your whim, you are going to have to do things you don't like, and you are going to have to compromise.
TL;DR: playing outside: independence + creativity. Job: independence + compromise + humility + compassion.
None of that you learn by doing homework.