I think the employment relationship is like any other relationship in your life, you get out of it what you put into it. If you value it, you take care of it. If you don't, you generally lose it and usually you don't even realize you've lost it until it's over.
Where does it start to go wrong? In our own heads. When we think our companies should treat us better than they do, when we think we're not getting enough recognition or pay, when we believe we are not being treated fairly, we plant the seeds of our own unhappiness.
Employment, whether we admit it to ourselves or not, is a voluntary activity on both sides. Either party can walk away at any time (barring an employment contract or agreement). So wouldn't it be more effective to leave if we are so unhappy and can't make our employer treat us the way we think they should than it is to complain while still taking their money?
I've spent the last day assisting a manager who is dealing with an employee who can't seem to stop himself from talking to the company's customers in a negative way about how the company operates. The company recently made an operational change that was discussed and agreed to in advance with the employees involved (including this employee). The first day the change was implemented this employee, instead of trying to make sure the change worked for both himself and his employer or even just waiting to see what impact the change would have on him, immediately started "sharing" his negative thoughts with "his" customers, coworkers, and even in an inappropriate way with other company managers. His manager, in response to the problems he was creating for the company by involving customers & coworkers, sent him home to spend his time off thinking about whether he really wanted to work for this company. How will it end? Badly unless and until this employee figures out that if he can't be trusted to back his company up in public (he can discuss his concerns behind closed doors with the management staff), he will not be allowed back to work.
Today's lesson? Disloyalty to your employer hurts you more than it will ever hurt them. You'll be gone and they will still be standing. So if you are truly unable to restrain yourself from acting against and talking badly about your employer while onsite and on the clock, it's probably time to voluntarily change your job before the choice is no longer yours to make.