Some workers require oversight to be productive, and for some it just helps. This means you get the most out of your work force, and can also hire workers who can't manage themselves. But managers also abstract trust and responsibility from multiple staff to one staff, help organize workflow, and ensure proper communication across teams. It's a simple matter of fact that some work is more fun, some people communicate better, and people don't organize themselves. Add to this the coaching and mentoring factor of a good manager, and it's a no-brainer.
Granted, what most employees fail to understand is if you have a manager, the company has already deemed you need one, and you're practically paying for your own overhead. Good managers are hard to come by, and are expensive. But businesses desperately need good managers because they solve most staffing issues. In other words, if you stop being complacent and just behave like a manager, chances are you will become one.
Here is how it's done: You start by managing yourself and removing your own overhead. Then you start taking care of other responsibilities because you can't help it. Know what needs to get done, understand the big picture, and just help accomplish it from the side. And when you provide relevant insight about how to improve something, put out a fire, or organize a project, you're already manager material. Your goal is to replace your manager without actually replacing him, without being the boss, without pissing anyone off, and without higher pay. You just made your bosses job easier, increased the value of everyone else, and ensured work got done. If your company doesn't give you a raise, you're at the wrong company.
Here is how it isn't done: You keep relying on your manager to keep you in check. You only accomplish your minimum requirements. You blame training for not being able to do anything else. You feel entitled for a raise just by being there for a long time.
Both of the above are exaggerated to emphasize two opposites, but most people are somewhere in between. Of course, if you're not manager material and you suck at your job, the likelihood is you will get fired, so it's perfectly okay to be complacent and just do good work. But the point is, you have your manager to thank for your straight forward and fairly comfortable job, and at the end of the day, his/her salary is practically coming out of yours.